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CaMoO 4 :Pr3+ thermochromic phosphors with diverse thermal responses for temperature sensing were prepared by the traditional solid-phase reaction method. The typical CaMoO 4 :Pr3+ had scheelite structure belonging to tetragonal crystal system and space group of I 4 1 / a (88). Pr3+ ions can be easily substituted for Ca2+ ions of host CaMoO 4 because of similar ionic radius. CaMoO 4 : 1.5% Pr3+ have the block structure with mean size of 6.84 μm. The E g (∼3.93 eV) value of pure CaMoO 4 is bigger than that (∼3.65 eV) of CaMoO 4 : 1.5%Pr3+, attributing to the existence of intermediate defect energy levels. Appropriate Pr3+ doping concentration is 1.5%, and the concentration quenching phenomenon can be explained by the concrete electric multipole type of d-d interaction. The emission peak at ∼605 nm from 1D 2 →3H 4 transition have a good thermal stability of 99.452%@423 K, while the wide band centered at ∼490 nm from 3T 1,2 → 1A 1 transition in the MoO 4 2− complex and 3P 0 →3H 4 transition in Pr3+ have a poor thermal stability of 27.572%@423 K. Calculated activation energy is 0.239 eV. Temperature-dependent FIR for optical thermometry was constructed due to their diverse thermal responses. CaMoO 4 : Pr3+ phosphor had good relative sensitivities of 2.216%, 0.969% and 0.932% based on FIR of I 605 nm /I 490 nm with Boltzmann distribution, modified Boltzmann distribution and exponential equation fitting. Thermochromic behavior and thermal quenching mechanism are investigated. The obtained relative sensitivity is better than that of most phosphors, implying that CaMoO 4 : Pr3+ has a potential for application in optical thermometry. [ABSTRACT FROM AUTHOR]

In this paper, a novel red-emitting persistent phosphor, Cd3Ga2Ge3O12:Pr3+, was successfully synthesized by the traditional method of a solid-phase reaction. The phase purity, photoluminescence, and persistent luminescence were successfully studied in detail. It was revealed that the photoluminescence spectra of as-prepared samples exhibit a series of emission peaks centered at 478, 561, 610, and 660 nm, corresponding to the 3P0 → 3H4, 3P2 → 3H6, 3P0 → 3H6, and 3P0 → 3H4 transitions of Pr3+, respectively. It was noted that the persistent luminescence of Cd3Ga2Ge3O12:0.0015Pr3+ could be recorded for 5580 s, showing excellent luminescent properties. Accordingly, with the help of thermoluminescence spectra, a feasible mechanism for the Cd3Ga2Ge3O12:Pr3+ sample is proposed and explored to explain its excellent persistent luminescence properties. The results show that the material has outstanding anti-counterfeiting properties. [ABSTRACT FROM AUTHOR]

In this paper, a novel red-emitting persistent phosphor, Cd3Ga2Ge3O12:Pr3+, was successfully synthesized by the traditional method of a solid-phase reaction. The phase purity, photoluminescence, and persistent luminescence were successfully studied in detail. It was revealed that the photoluminescence spectra of as-prepared samples exhibit a series of emission peaks centered at 478, 561, 610, and 660 nm, corresponding to the 3P0 → 3H4, 3P2 → 3H6, 3P0 → 3H6, and 3P0 → 3H4 transitions of Pr3+, respectively. It was noted that the persistent luminescence of Cd3Ga2Ge3O12:0.0015Pr3+ could be recorded for 5580 s, showing excellent luminescent properties. Accordingly, with the help of thermoluminescence spectra, a feasible mechanism for the Cd3Ga2Ge3O12:Pr3+ sample is proposed and explored to explain its excellent persistent luminescence properties. The results show that the material has outstanding anti-counterfeiting properties. [ABSTRACT FROM AUTHOR]

The industrially important rare-earth elements (REE) are contained in pronounced quantities (up to 1 wt %) in the apatite of the Kola Peninsula, which dictates interest in their extraction. The extraction of rare-earth elements with 100% tributyl phosphate from solutions obtained by dissolving the phosphate concentrate of REE isolated from the nitrogen phosphate solutions of apatite processing has been considered. It was found that to prevent precipitation, the extractant (100% tributyl phosphate) should be preliminarily saturated with nitric acid to a concentration C1 = (αC3–C2 + C4)/α, where C2, C3, and C4 are the nitric acid concentrations (mol/dm3) in the initial solution, saturated extract, and raffinate, respectively; α is the flow rate ratio of the organic and aqueous phases; and C1 is the minimum concentration of nitric acid in the fresh organic phase at which there is no precipitation of REE phosphates at the first stages along the course of the organic phase. A combined technology has been proposed, including the stage of REE extraction from a nitrogen phosphate solution, followed by the transfer of some part of the extract saturated with REE oxides to 150–160 g/dm3 as an initial solution for separation of REEs into groups (at the Pr–Nd or Nd–Sm boundary). The cerium group elements are concentrated in the raffinate of the separation cascade (wt %): La2O3 38.1, CeO2 61.2, Pr6O11 0.7; the didymium concentrate Pr6O11 + Nd2O3 is concentrated in the extract. [ABSTRACT FROM AUTHOR]

In this paper, we examine the purity level and impurity composition of rare-earth metals represented at the Exhibition–Collection of Extrapure Substances and present estimates of the average and total concentrations of elemental impurities in the purest samples. We analyze the impurity composition of the entire array of rare-earth metals and contributions of particular groups of impurities. [ABSTRACT FROM AUTHOR]

The coordination of rare-earth metal ions (Ln3+) to polyoxometalates (POM) is regarded as a way of modifying and controlling their properties, such as single-molecular magnetism or luminescent behavior. The half-sandwich complexes of Ln3+ with monolacunary Keggin POMs (Ln3+/POM = 1:1) are of particular interest, since the Ln3+ retains its ability to coordinate extra ligands. Thus, the knowledge of the exact structures of 1:1 Ln/POM complexes is important for the development of reliable synthetic protocols for hybrid complexes. In this work, we isolated three 1:1 Gd3+/POM complexes of the general formula Cat4Gd(PW11O39)·xH2O (Cat = K+ or Me4N+). Complex (Me4N)2K2[Gd(H2O)2PW11O39]·5H2O (1) is polymeric, revealing a layered structural motif via bridging Gd3+ and K+ ions. Complexes (Me4N)6K2[Gd(H2O)3PW11O39]2·20H2O (2) and (Me4N)7K[Gd(H2O)3PW11O39]2·12H2O (3) are classified as dimeric; the difference between them consists of the different crystal packing of the polyoxometalates, which is induced by a variation in the cationic composition. Isostructural complexes have also been characterized for praseodymium, europium, terbium and dysprosium. The coordination number of Ln3+ (8) persists in all the compounds, while the binding mode of the POM varies, giving rise to different architectures with two or three H2O co-ligands per Ln3+. However, whatever the particular structure and exact composition, the {Ln(PW11O39)} moieties are always involved in bonding with each other with the formation either of polymeric chains or dimeric units. In water, these aggregates can dissociate with the formation of [Ln(H2O)4PW11O39]4-. This behavior must be taken into account when choosing L for the design of hybrid {Ln(L)POM} complexes. [ABSTRACT FROM AUTHOR]

The 2-phosphaethynolate has received particular attention and displayed various reaction patterns due to its ambident property. In this work, the reactivity of monoanionic bidentate anilidophosphine PN ligand (PN: N-(2-(diisopropylphosphanyl)-4-methylphenyl)-2,4,6-trimethyl anilide) supported (PNMe3)2PrIIICl (2A) and (PNMe3)2TbIIICl (2B) with NaOCP(dioxane)2.5 by salt elimination reaction is described. The reactions yield corresponding praseodymium and terbium phosphaethynolate complexes: (PNMe3)2PrIIIOCP (3A) and (PNMe3)2TbIIIOCP (3B), respectively. These two complexes feature a preferential O-bound terminal adduct. Magnetic data analysis reveals that praseodymium and terbium chloride and phosphaethynolate complexes showed a strong temperature dependence. All the complexes have been characterized by various measurement means, including NMR, UV spectroscopies, FT-IR spectrum as well as X-ray single crystal crystallography. For comparison, bond analyses of all the complexes collected from experimental and computational approaches are conducted in detail. [ABSTRACT FROM AUTHOR]

The reaction of triphenylcyclopentadienyl potassium with praseodymium and erbium chloride tetrahydrofuranates gives, depending on the reactant ratio, tetranuclear ate complexes, [{(Ph3C5H2)-Pr(THF)}2(µ2-Cl)2(µ3-Cl)3K]2(C7H8)4 (I) and [{(Ph3C5H2)Er(THF)}2(µ2-Cl)2(µ3-Cl)3K(THF)]2 (III), or binuclear ate complexes [(Ph3C5H2)2LnCl(KCl)]2 Ln = Pr (II), Er (IV) (CCDC nos. 2224244 (I), 2224243 (II), 2224245 (III), 2224242 (IV)). The structurally similar complexes I and III are based on the {[Ln2(µ-Cl)3]2(µ-Cl)2K2} core, and in III, the potassium cation is additionally coordinated to the THF molecule. The isostructural complexes II and IV have the binuclear [Ln(µ-Cl)2K]2 core. [ABSTRACT FROM AUTHOR]

Optical constants n and k of a polycrystalline film of aluminum alloy and 2.54 at % praseodymium were measured at room temperature. Based on these data, optical-conductivity spectra were obtained for a clean and oxidized alloy surface. When analyzing the results of comparing these spectra with the model ones, the electronic characteristics of optical transitions, including the characteristics of surface states of electrons, were obtained. It is shown that the conduction band of an alloy with a clean surface is split to a minimum extent. The oxygen-adsorption heat values on the surface of an Al–2.54 at % Pr alloy film have been calculated. The equilibrium position of the adsorption–desorption processes of an alloy film at room temperature is significantly shifted towards desorption. [ABSTRACT FROM AUTHOR]

The sediment deposited behind a dam (DS) and its inorganic materials (IM-DS) were characterized and used for the removal of praseodymium (Pr) from aqueous solutions. Quartz, albite, and kaolinite were found in the sediment by X-ray diffraction. Kinetic data fit well to a pseudo second-order model, the equilibrium time for DS and IM-DS was 2 h and 3 min, respectively, and the adsorption capacity was higher for Pr/DS (q e = 4.91 mg/g) than for Pr/IM-DS (q e = 3.01 mg/g) in these conditions. Pr/DS and Pr/IM-DS data isotherms were in agreement with the Langmuir–Freundlich model and the maximum adsorption capacities were 4.95 and 4.01 mg/g, respectively. Both processes are exothermic (enthalpy change, Δ H 0 = −22.8 and −21.8 kJ/mol for DS and IM-DS, respectively), the increase of the randomness is small, and the feasibility and spontaneity are low. Praseodymium was desorbed by ethylenediaminetetraacetic acid disodium (EDTA-Na 2), sodium chloride, nitric, citric, and humic acids solutions, and one hundred percent of praseodymium was desorbed by the EDTA-Na 2 solution. The Pr 2 (EDTA) 3 (praseodymium ethylenediaminetetraacetate) complex was completely desorbed from both materials (DS and IM-DS). Distribution coefficients (K D) depend upon praseodymium concentration, temperature, pH, and the kind of adsorbent. Chemical reactions of praseodymium with kaolinite and iron minerals could explain the adsorption. [ABSTRACT FROM AUTHOR]

With their dipole‐forbidden 4f transitions, lanthanides doped in nanoparticles promise high excited state lifetimes and quantum yields that are required for applications such as composite lasers or nanoscale quantum memories. Quenching at the nanoparticle surface, however, severely reduces the lifetime and quantum yield and requires resource‐consuming experimental optimization that could not be replaced by simulations due to the limitations of existing approaches until now. Here, a versatile approach is presented that fully accounts for spatiotemporal dynamics and reliably predicts the lifetimes and quantum yields of lanthanide nanoparticles. LiYF4:Pr3+nanoparticles are synthesized as a model system, and the lifetimes of a concentration series (≈10 nm, 0.7−1.47 at%) are used to match the model parameters to the experimental conditions. Employing these parameters, the lifetimes and quantum yields of a size series (≈5 at%, 12−21 nm) are predicted with a maximum uncertainty of 12.6%. To demonstrate the potential of the model, a neutral shell is added around the core particles in the model which extends the lifetime by up to 44%. Furthermore, spatiotemporal analysis of single nanoparticles points toward a new type of energy trapping in lanthanide nanoparticles. Consequently, the numerical optimization brings applications such as efficient nanoparticle lasers or quantum memories within reach. [ABSTRACT FROM AUTHOR]

A sensitive and selective method of analysis was constructed by the the combination of praseodymium oxide and carbon nanotubes. The charge transfer resistance (Rct) values of 109 in 1 × 10−3 M K3[Fe(CN)6] and 79 Ω in 5 × 10−6 M dopamine indicate that Pr6O11@MWCNTs/GCE enables an excellent electron pathway between electrolyte and electrode. The platform was successfully applied for the determination of dopamine in the presence of tramadol, paracetamol and ascorbic acid. The platform exhibited a remarkable decrease in ▵Ep for DA. A dynamic linear range from 1.2 × 10−9 M to 1.8 × 10−5 M was obtained with an LOD of 1.0 × 10−10 M. Such a sensitive and selective method of analysis makes Pr6O11@MWCNTs/GCE of high interest to observe trace level of DA with good accuracy and precision. [ABSTRACT FROM AUTHOR]

Lanthanides (Ce, Pr, Nd and Gd) 1, 3, 5 and 10 wt% of each were loaded into a pristine sodium aluminium phosphate glass matrix in order to simulate the immobilization of minor actinides (Am, Np, Cm) produced from spent nuclear fuel reprocessing. The optical parameters pertaining to these glasses were derived from the diffuse reflectance spectra. The systematic dependence of the physical and structural properties of these glasses on the dopants and the concentration of the latter was studied by XRD and Raman spectroscopy. The results on Rare Earth (RE) doped sodium aluminium phosphate are being reported for the first time. The physical parameters such as density, molar volume and oxygen packing density were evaluated. The XRD patterns showed the absence of any crystalline phase in these glasses. The relative % areas of (PO3)−2(Q2) bonds increase, whereas Q0 and Q1 tend to decrease with the addition of lanthanide oxides as compared to the pristine glass. The addition of different lanthanide oxides was found to depolymerize the network by forming more Q2 short chains. The results showed that the band gap energy (Eg) depends strongly on the cation field strength (CFS) of the lanthanides. The band gap energy decreases with an increase in the lanthanide concentration in the glass matrix. Praseodymium-doped glasses showed the highest Eg values (5.28–5.23 eV). The photoluminescence spectra confirm the characteristic excitation and emission peaks for the cations Ce+3, Pr+3 and Gd+3 and their variation with concentration was analysed. [ABSTRACT FROM AUTHOR]

The red persistent luminescence phosphors SrS: Eu x 2 + , Pr y 3 + (x = 0∼0.001, y = 0∼0.003) were synthesized by the solid-state reaction method in a weak reducing atmosphere of active carbon. The synthetic parameters, photoluminescence characteristics, and dynamic properties of thermoluminescence of the phosphors were studied systematically. According to the results of photoluminescence spectra of SrS: Eu x 2 + , Pr y 3 + , the energy level scheme of the phosphors was confirmed quantitatively. Based on the studies of the scanning electron microscope (SEM), UV-Visible absorbance spectra, afterglow decay curves, thermoluminescence(TL) spectra, and X-ray photoelectron spectroscopy (XPS) spectra, we found that the SrS: Eu 0.0001 2 + , Pr 0.003 3 + (SSEP) phosphor presented the best persistent luminescence property, which mainly resulted from its outstanding absorbance characteristic, deeper depth of V S ⋅ ( V S ⋅ ⋅ ) defects, and fewer defect concentration belonging to the higher-order kinetics. Those comprehensive results deduced that a complex defect V S ⋅ ( V S ⋅ ⋅ )- V ′ ′ Sr should present in the Eu2+ doping phosphors, and the Pr3+ doping will produce Pr Sr ⋅ defects, which can suppress the formation of V S ⋅ ( V S ⋅ ⋅ ) defects and increase their energy depth. [ABSTRACT FROM AUTHOR]

We report on the high-resolution Fourier spectroscopy study of KY3F10:Pr3+ crystals. The analysis of the transmission and luminescence spectra allowed us to refine and supplement the information on the crystal-field levels of the Pr3+ ion. The value of the hyperfine splitting of the ground state of Pr3+ in the KY3F10 cubic host is estimated. The observed shape of the spectral lines indicates the presence of defects in the sample under study. [ABSTRACT FROM AUTHOR]

The praseodymium Pr3+ doped at Bi site of Ba0.1Bi0.9(Ti0.9Zr0.1)0.1Fe0.9O3, under low concentrations (0%, 0.1%, 0.5% and 1% abbreviated as BBTZF0, Pr-BBTZF001, Pr-BBTZF005 and Pr-BBTZF01, respectively) were prepared by the solid-state reaction method. A detailed investigation has been made on structural, microstructural, ferroelectric and dielectric properties of Ba0.1(Bi1−xPrx)0.9(Ti0.9Zr0.1)0.1Fe0.9O3 ceramics. Rietveld refinement fitting revealed that the structure of these ceramics, at room temperature is rhombohedral with space group R3c. The cell volume decreased with increasing Pr-content due to the smaller ionic radius of the Pr. Temperature dependence of the dielectric constant (ε′r) of all prepared ceramics showed anomaly around TN (antiferromagnetic transition temperature); thus suggesting a magneto-electric coupling in these materials. The shift of TN with frequency is attributed to the Maxwell Wagner relaxation rather than the relaxor behavior. The P–E loop study shows the improved ferroelectric behavior and the reduced leakage current density with Pr doping. Moreover, the energy storage properties showed a clear enhancement upon the increase of the Pr concentration. The recoverable energy storage density (Wrec) of 2.75 J cm−3 with energy storage efficiency (η) of 44.52% was achieved for Pr-BBTZF01. [ABSTRACT FROM AUTHOR]

Using a soft chemical process that involves nitrates and heat annealing, nanoparticles of undoped ZnO and praseodymium, aluminum-codoped ZnO may be produced. XRD, SEM with EDS, and FTIR analysis determine nanocatalyst structures, morphologies, and chemical bonding. PL and UV spectroscopy examines optical characteristics. The peak in the FTIR spectral line at 714 cm -1 in the study indicates M-O stretching in the samples and ZnO's interaction with the Pr and Al matrix. XRD patterns indicated prepared nanoparticles with nanosizes ranging from 40.07 to 38.65 to 36.84 to 38.87 to 39.91 nm. SEM analyzed nanoparticle size, shape, and interaction with the Pr and Al matrix. EDS determined NPs purity. UV-vis spectra of ZnO-Pr/Al nanocomposites showed UV absorption similar to ZnO nanoparticles. Doping ZnO with Pr and Al shrinks the bandgap and slows photogenerated electron-hole pair recombination without changing its crystalline structure. [ABSTRACT FROM AUTHOR]

Little information is published on the hardness and corrosion resistance properties of WC-Mn-Cu-Ni alloys infiltrated by an NdPrFeB alloy. Is iron-neodymium-praseodymium inter-metallic compound a desirable choice for a binder for liquid sintering or spontaneous infiltration at high temperatures? Also, is it an opportunity to study the effect of the particle size (d < 30 μm) and the percentage of addition (<5%) of neodymium and praseodymium on the mechanical and electrochemical properties of the composite WC-Cu-Ni-Mn/binder? These inter-metallic composites associating elements of different sizes and electronegativities make it possible to have metallic bonds, but also localized interactions, of the covalent type, between metals and semi-metallic element. The influence of the mechanisms of dissolution and progressive precipitation intervening in the process of densification in the liquid phase allows for obtaining micro-hardness with a value of 1580 HV0.3 and a relative density of 0.798. The micrographs reveal additional information concerning the strong chemical activity of Nd and Pr. The advantage of using the NdPrFe alloy is to take advantage of both the qualities of each element via the coupling of the conduction electrons of the two elements. The behavior of the composite sample in an aggressive (1 M NaOH) medium was examined. Electrochemical parameters determined from Tafel lines show a significant diminution of I corr when a grain size decreases. For the sample elaborated by spontaneous infiltration the polarization resistance increases to 3686 Ωcm2 and the addition of 4–5 wt% of rare earth (RE) is recommended. In relations to their composition and hardness, we can consider these materials as candidates for magnetic drilling tools. [ABSTRACT FROM AUTHOR]

The study investigates the ability of synthetic ZrSiO 4 to host the combined occupancy of Pr3+/PO 4 3− in its tetragonal crystal lattice. Sol-gel method has been utilized to synthesize a series of Pr3+/PO 4 3− additions in SiO 2 –ZrO 2 binary oxides and the feasibility of the resultant to transform into a ZrSiO 4 by the influence of thermal treatment were investigated through series of analytical techniques. The overall results indicated the feasibility of ZrSiO 4 lattice to host a maximum of 10 mol.% Pr3+/PO 4 3− to retain a unique solid solution beyond which the crystallization of PrPO 4 as a secondary phase is noticed. The temperature effect has played a pivotal role in the phase behaviour of SiO 2 –ZrO 2 binary oxides due the invariable range maintained in the Pr3+/PO 4 3− additions. The data obtained from the absorption spectra, luminescence, lifetime decay measurements, morphological, magnetic and mechanical analysis of the investigated systems ensured the significance of phase composition to yield the desired properties. Formation of ZrSiO 4 solid solution until 10 mol.% saturation occupancy limit of Pr3+/PO 4 3− beyond which the crystallization of PrPO 4 is witnessed. [Display omitted] [ABSTRACT FROM AUTHOR]

Although field emission devices are inherently robust to high temperature and radiation environments as well as have high switching speeds, their development has been hindered by high voltages that are typically required for their operation. In this work, we investigate the effect of thin-film praseodymium (Pr) coating on the emission characteristics of a lateral gold (Au) field emitter array. Because Pr has a significantly lower work function than Au, it is expected to increase the field emission measured current. Pr is deposited onto the device via thermal angled evaporation in a custom-built vacuum chamber with in situ electrical characterization capability. Our experiments demonstrate that a 10 nm-thick Pr layer reduces the turn-on voltage by almost half compared to the noncoated Au structure. These results are promising for the development of power-efficient, low voltage field emission electronics. [ABSTRACT FROM AUTHOR]

Catalytic methane (CH4) dry reforming (MDR) reaction proceeds with the formation of carbon; hence the effects of the catalyst preparation method on the type of carbon are worth investigating. This study investigated the performance of 20 wt% nickel praseodymium (III) oxide (20 wt% Ni/Pr2O3) catalysts prepared by incipient wetness impregnation (IWI), ultrasonic wet impregnation (US-WI), and Pechini sol–gel (PSG) methods. The catalysts crystallite size was approximately 21.3 nm, 21.3 nm, and 10.6 nm, for IWI, US-WI, and PSG catalysts, respectively. Study of the temperature effecton the MDR system showed that higher temperatures favored the MDR reaction with the side reaction playing vital roles. The catalyst synthesized by the PSG method showd higher carbon gasification rate with the stability up to 24 h, whereas catalysts from other synthesis methods were only active for less than 2 h, which could be due to the formation of higher amount of filamentous carbon, balance in oxygen species, and the smaller crystallite size of the PSG-20 wt% Ni/Pr2O3. The PSG-20 wt% Ni/Pr2O3 catalyst accumulated more filamentous carbon than graphitic carbon. In contrast, the IWI and US-WI catalysts accumulated mainly graphitic carbon which encapsulated the Ni0 sites, resulting in excess carbon deposition and reactor clogging within 2 h on stream. [ABSTRACT FROM AUTHOR]

A straightforward ferrocyanide immobilization on the surface of graphene oxide (GO) was conducted for rapid and efficient adsorption capacity for lanthanum and praseodymium from an aqueous solution. The GO was mixed with 1-methyl imidazole in the presence of epichlorohydrin to form GO-imidazole-Cl and thereafter suspended in a potassium ferrocyanide solution to fabricate GO-imidazole-FeCN. The prepared materials were characterized with different advanced techniques confirming the preparation method. The adsorption ability of GO-imidazole-FeCN towards La(III) and Pr(III) ions was evaluated. Moreover, the adsorption isotherm showed that the sorption process was fitted with the Langmuir isotherm model with a considerable maximum adsorption capacity of 781.25 mg g−1 for La(III) and 862.07 mg g−1 for Pr(III). The thermodynamic studies showed that the adsorption of both metal ions was spontaneous and endothermic. In addition, the adsorbent showed excellent adsorption–desorption behavior over 5 times, suggesting that GO-imidazole-FeCN may be considered a potential candidate for La(III) and Pr(III) removal from different metal ions which present in fission products. [ABSTRACT FROM AUTHOR]

The red persistent luminescence phosphors SrS: Eu x 2 + , Pr y 3 + (x = 0∼0.001, y = 0∼0.003) were synthesized by the solid-state reaction method in a weak reducing atmosphere of active carbon. The synthetic parameters, photoluminescence characteristics, and dynamic properties of thermoluminescence of the phosphors were studied systematically. According to the results of photoluminescence spectra of SrS: Eu x 2 + , Pr y 3 + , the energy level scheme of the phosphors was confirmed quantitatively. Based on the studies of the scanning electron microscope (SEM), UV-Visible absorbance spectra, afterglow decay curves, thermoluminescence(TL) spectra, and X-ray photoelectron spectroscopy (XPS) spectra, we found that the SrS: Eu 0.0001 2 + , Pr 0.003 3 + (SSEP) phosphor presented the best persistent luminescence property, which mainly resulted from its outstanding absorbance characteristic, deeper depth of V S ⋅ ( V S ⋅ ⋅ ) defects, and fewer defect concentration belonging to the higher-order kinetics. Those comprehensive results deduced that a complex defect V S ⋅ ( V S ⋅ ⋅ )- V ′ ′ Sr should present in the Eu2+ doping phosphors, and the Pr3+ doping will produce Pr Sr ⋅ defects, which can suppress the formation of V S ⋅ ( V S ⋅ ⋅ ) defects and increase their energy depth. [ABSTRACT FROM AUTHOR]

The effect of adding Praseodymium (Pr) with different percentages of 0.1, 0.3, 0.5, and 1% mass % on the solidification characteristics, microstructure, strength, impact energy, and hardness of ADC12 commercial alloy was evaluated. Examination of the three-dimensional morphology of Si by scanning electron microscopy (SEM) showed that by adding different percentages of Pr, the flake-like and needle structure of the eutectic Si did not change significantly. Cooling curve thermal analysis (CCTA) depicted that the growth temperature of Si decreased by less than 0.4° C, which was consistent with no change in the morphology of Si. The ultimate tensile strength, elongation percentage, impact energy, and hardness values were changed by 2.5%, 11.3%, 0.9%, and 1.5%, respectively, after adding 1 mass % Pr. Most of the fracture surfaces of the specimens were composed of cleavage, which indicated a brittle fracture mode proportional to small percentages of elongation. Based on the results, it can be concluded that Pr does not play the role of a modifier element for eutectic Si. The ratio of Pr radius to Si is 1.56, slightly less than the proposed value of 1.65 to modify based on growth theory. But elements with lower atomic radius ratios have changed Si. Therefore, growth theory alone can not be a reliable criterion for evaluating modification. [ABSTRACT FROM AUTHOR]

AZ31B has the advantages of high specific strength, low melting point and good toughness, but one of the significant disadvantages is poor corrosion resistance. This topic designed and prepared a corrosion-resistant composite coating of organic polymer phytic acid and rare earth praseodymium salt based on this characteristic. The test results show that the corrosion resistance of the PA/Pr composite coating is more potent than that of a single phytic acid conversion coating, and the surface of the composite layer is clustered particles with good compactness. The conversion coating mainly consists of praseodymium hydroxide, oxide and some phytate compounds. In addition, density functional theory (DFT) was used to analyze the inhibition mechanism of phytic acid; Molecular dynamics (MD) was used to evaluate the adsorption characteristics of phytic acid on metal substrates and rare earth metal oxides. [ABSTRACT FROM AUTHOR]

The fabrication of electrode material with unique physiochemical properties is significant to enhance electrochemical performance. In this work, we synthesized praseodymium vanadate (PrVO 4) through green deep eutectic solvents (DES) by the solvothermal approach and explored it as an electrochemical sensor for furaltadone (FLD) detection. The as-prepared PrVO 4 was characterized by using appropriate microscopic and spectrophotometric techniques. The modification of the electrode on PrVO 4 showed excellent electrochemical performance due to its high conductivity, active sites, and fast electron transfer ability. The PrVO 4 -modified electrode displayed a dynamic linear range (0.008–91 μM), trace-level detection limit (0.002 μM), high sensitivity (4.276 μA µM–1 cm–2), and strong selectivity for FLD detection under optimum experimental conditions. The practical applicability of PrVO 4 modified electrode was successfully investigated for the effective determination of FLD in pond water, human urine, and fish samples, revealing its potential application for real samples analysis. This work provide applicable guidelines for the design and development of DES-based electrode materials for the electrochemical sensor application. [ABSTRACT FROM AUTHOR]

Compressed hydrogen-rich compounds have been verified extensively by theoretical scientists for finding high-temperature superconductivity. Although some experiments confirm these findings, their requirement of extremely high critical pressure condition ( 100 GPa ≲ P c ) makes them impossible to apply in daily life. The main purpose of present work is to help finding materials with high-temperature superconductivity at low pressures. For this purpose, we consider two graphene sheets with sine form corrugations whose honeycomb patterns are exactly on top of each other with some doped molecules intercalated into sheets. The free energy of valence electrons of total atoms is computed for doped molecules PrH 6 , PrH 7 , PrH 8 , and PrH 9 , separately. Our calculations indicate a second-order phase transition for PrH 9 at critical temperature T c = 179.01 K with applying no external pressure, while no phase transition is observed for other doped molecules. This high-temperature electronic structural stability is 46 K greater than the T c of the cuprate materials which are the highest-temperature superconductors at low pressures. We guess this phase transition is a superconductivity transition due to the observation of Meissner effect in magnetic susceptibility diagram. [ABSTRACT FROM AUTHOR]

The redox reactions of various lanthanide metals with 3-(4-pyridyl)pyrazole (4-PyPzH) or 3-(3-pyridyl)pyrazole (3-PyPzH) ligands yield the 2D network ∞ 2 [Eu(4-PyPz)2(Py)2] containing divalent europium, the 3D frameworks ∞ 3 [Ln(4-PyPz)3] and ∞ 3 [Ln(3-PyPz)3] for trivalent cerium, praseodymium, neodymium, holmium, erbium, and thulium as well as ∞ 3 [La(4-PyPz)3], and the 2D networks ∞ 2 [Ln(4-PyPz)3(Py)] for trivalent cerium and thulium and ∞ 2 [Ln2(4-PyPz)6]·Py for trivalent ytterbium and lutetium. The 18 lanthanide coordination polymers were synthesized under solvothermal conditions in pyridine (Py), partly acting as a co-ligand for some networks. The compounds exhibit a variety of luminescence properties, including metal-centered 4f–4f/5d–4f emission in the visible and near-infrared spectral range, metal-to-ligand energy transfer, and ligand-centered fluorescence and phosphorescence. The anionic ligands 3-PyPz− and 4-PyPz− serve as suitable antennas for lanthanide-based luminescence in the visible and near-infrared range through effective sensitization followed by emission through intra–4f transitions of the trivalent thulium, holmium, praseodymium, erbium, and neodymium. ∞ 2 [Ce(4-PyPz)3(Py)], ∞ 3 [Ce(4-PyPz)3], and ∞ 3 [Ce(3-PyPz)3] exhibit strong degrees of reduction in the 5d excited states that differ in intensity compared to the ligand-based emission, resulting in a distinct emission ranging from pink to orange. The direct current magnetic studies show magnetic isolation of the lanthanide centers in the crystal lattice of ∞ 3 [Ln(3-PyPz)3], Ln = Dy, Ho, and Er. [ABSTRACT FROM AUTHOR]

Praseodymium, the sixth-most abundant rare-earth element, is widely used in the aircraft industry for the elaboration of refractory substances, coloring materials, lighting equipment, and fiber optical cables. Living and non-living Arthrospira platensis biomass was applied for Pr(III) removal from aqueous solutions. In bioaccumulation experiments, the effect of Pr(III), introduced into the medium in a concentration range of 10–30 mg/L, on biomass productivity, biochemical composition, and antioxidant activity was assessed. The biomass showed high accumulation capacity (more than 99%) toward Pr(III). Supplementation of the cultivation medium with Pr(III) led to a decrease in carbohydrate and lipid content, but it did not significantly influence biomass productivity or the content of proteins and pigments. In experiments with non-living biomass, the effect of pH, Pr(III) concentration, temperature, and contact time on the efficiency of metal removal was investigated. The maximum uptake of Pr(III) was achieved at pH 3.0 after 3.0 min of interaction. The equilibrium data were explained using the Langmuir and Freundlich models, while the kinetics of the process was described by applying pseudo-first-order, pseudo-second-order, and Elovich models. The maximum sorption capacity of Arthrospira platensis biomass calculated from the Langmuir model was 99.3 mg/g. According to the thermodynamic calculations, the process of Pr(III) removal was spontaneous and exothermic in nature. The obtained data can be used for the development of environmentally-friendly technology for Pr(III) recovery from wastewater as well as to understand the effect of Pr(III) on aquatic organisms. [ABSTRACT FROM AUTHOR]

The raw materials of La3+ ion-doped Y0.998Pr0 002InGe2O7 phosphor were mixed by a vibration mill method, then calcined at 1200 °C for 10 h in air by a solid-state reaction. Regardless of the La3+ ion doping concentration, the La3+ ion did not change the crystal structure, but the luminescence properties including both the excitation and emission intensities did change. The saturation emission intensity excited by a deep UV light for the phosphor increased when the La3+ ion doping content was 10 mol%. As the La3+ ion with a large radius was introduced as a substitute for the Y3+ ion with a small radius in the Y0.998Pr0.002InGe2O7 system, an increase in compressive strain led to a decrease in oxygen vacancy concentration, which changed the emission intensity of ¹D2→³H4 and ³ P0→ ³ H4 radiations for Pr3+ ion 4f-4f transition. The Commission Internationale de L'Eclairag (CIE) color coordinates of the La3+ ion-doped Y0.998Pr0.002InGe2O7 phosphor shifted slightly, but all were in the white light region at various La3+ ion doping contents. This provides an intelligent method for improving the luminescence properties of Y0.998Pr0.002InGe2O7 single-phased white light-emitting phosphors for white LEDs. In addition, various emission intensity ratios of the ¹D2→ .³ H4 and ³P0→ ³H4 radiations enable the phosphors to be applied to oxygen gas sensors [ABSTRACT FROM AUTHOR]

Lanthanides in the trivalent oxidation state are typically described using an ionic picture that leads to localized magnetic moments. The hierarchical energy scales associated with trivalent lanthanides produce desirable properties for e.g., molecular magnetism, quantum materials, and quantum transduction. Here, we show that this traditional ionic paradigm breaks down for praseodymium in the tetravalent oxidation state. Synthetic, spectroscopic, and theoretical tools deployed on several solid-state Pr4+-oxides uncover the unusual participation of 4f orbitals in bonding and the anomalous hybridization of the 4f1 configuration with ligand valence electrons, analogous to transition metals. The competition between crystal-field and spin-orbit-coupling interactions fundamentally transforms the spin-orbital magnetism of Pr4+, which departs from the Jeff = 1/2 limit and resembles that of high-valent actinides. Our results show that Pr4+ ions are in a class on their own, where the hierarchy of single-ion energy scales can be tailored to explore new correlated phenomena in quantum materials. Trivalent lanthanides are typically described using an ionic picture that leads to localized magnetic moments. Here authors show that the "textbook" description of lanthanides fails for Pr4+ ions where the hierarchy of single-ion energy scales can be tailored to explore correlated phenomena in quantum materials. [ABSTRACT FROM AUTHOR]

Unexpectedly, a mixture of bismuth N,N′-bis(2,6-diisopropylphenyl)formamidinates in three different oxidation states namely, [Bi I2 (DippForm)2] (1), [Bi II2 (DippForm)2(C6F5)2] (2) and [BiIII(DippForm)2(C6F5)] (3), together with [Pr(DippForm)2F(thf)]·PhMe (4), [p-HC6F4DippForm]·0.5thf (5), and a ring-opened tetrahydrofuran [o-HC6F4O(CH2)4DippForm] (6) was obtained by the reaction of an excess of praseodymium metal with tris(pentafluorophenyl)bismuth, [Bi(C6F5)3]·0.5dioxane, and bulky N,N′-bis(2,6-diisopropylphenyl)formamidine (DippFormH) in tetrahydrofuran. Similar reactions between praseodymium metal, [Bi(C6F5)3]·0.5dioxane and 3,5-diphenylpyrazole (Ph2pzH), or 3,5-di-tert-butylpyrazole (tBu2pzH), yielded the paddlewheel dibismuthanes [Bi II2 (Ph2pz)4]·dioxane (7) and [Bi II2 (tBu2pz)4] (8) respectively. [ABSTRACT FROM AUTHOR]

A new glass series with nominal molar composition of 60B 2 O 3 + 30NaF + 10Al 2 O 3 co-doped with Dy3+ and Pr3+, synthesized by melt quench was reported. The influence of Rare Earth (RE) ratio variation on prepared glasses was investigated by using Fourier Transform Infra-Red spectroscopy, UV–Vis–NIR absorption spectroscopy, Photoluminescence, Decay curves and Density measurements. Their X-Ray Diffraction and FTIR spectra revealed the glassy nature and confirmed that AlO 6 , AlO 4 , BO 3 and BO 4 units are the main structural units of that matrix. A non-linear variation following the same trend for tetragonal borate units (N 4), Band gap, non-linear optical properties, Density, Molar Volume etc. was observed. Different optical parameters were obtained by UV–Vis–NIR spectroscopy. The Bonding parameter obtained from Nephelauxetic study indicated ionic nature of Dy3+ and covalent nature of Pr3+ ions. Photoluminescence excitation and emission spectra were recorded under variety of excitation wavelengths and corresponding color parameters were calculated using 1931 CIE standards. A detailed yellow to blue ratio analysis was reported as a function of RE ion concentration and excitation wavelengths. Composition DPNAB(x = 0.7) displayed the best performance with CIE coordinates (0.33, 0.37). Existence of Energy transfer from Dy3+ and Pr3+ was evidenced by the spectral overlap diagram and lifetime values obtained from fitting of Decay curves. From the obtained results, prepared glasses can be suggested for solid-state lighting devices like WLEDs and display devices. • Dysprosium (Dy3+) and Praseodymium (Pr3+) co-doped alumino-borate glasses were prepared. • FTIR exploration confirmed the existence of AlO 6 , AlO 4 , BO 3 and BO 4 units in the structure. • Optical transitions of Dy3+ and Pr3+ were observed. • Photoluminescence investigations predict the applicability of prepared glasses in tunable visible lighting applications. • Yellow to Blue (Y/B) ratio was discussed as a function of Dy3+concentration and excitation wavelengths. [ABSTRACT FROM AUTHOR]

Abdel-Magied AF, Abdelhamid HN, Ashour RM, Zou X, Forsberg K. Hierarchical porous zeolitic imidazolate frameworks nanoparticles for efficient adsorption of rare-earth elements. Shu Q, Khayambashi A, Wang X, Wei Y. Studies on adsorption of rare earth elements from nitric acid solution with macroporous silica-based bis (2-ethylhexyl) phosphoric acid impregnated polymeric adsorbent. Novel high-gluten flour physically cross-linked graphene oxide composites: hydrothermal fabrication and adsorption properties for rare earth ions. [Extracted from the article]

A series of strontium orthotitanate (Sr2TiO4) samples doped with 2% of a mole of europium, praseodymium, and erbium were obtained using the solid-state synthesis method. The X-ray diffraction (XRD) technique confirms the phase purity of all samples and the lack of the influence of dopants at a given concentration on the structure of materials. The optical properties indicate, in the case of Sr2TiO4:Eu3+, two independent emission (PL) and excitation (PLE) spectra attributed to the Eu3+ ions at sites with different symmetries: low – excited at 360 nm and high – excited at 325 nm, while, for Sr2TiO4:Er3+ and Sr2TiO4:Pr3+, the emission spectra do not depend on the excitation wavelength. The measurements of X-ray photoemission spectroscopy (XPS) indicate the presence of only one type of charge compensation mechanism, which is based on the creation of strontium vacancies in all cases. This suggests that the different charge compensation mechanisms cannot easily explain the presence of Eu3+ at two non-equivalent crystal sites. The photocurrent excitation (PCE) spectroscopy investigations, that have not been reported in the literature so far, show that among all the studied dopants, only Pr3+ can promote the electrons to the conduction band and give rise to electron conductivity. The results collected from the PLE and PCE spectra allowed us to find the location of the ground states of lanthanides(II)/(III) in the studied matrix. [ABSTRACT FROM AUTHOR]

A series of strontium orthotitanate (Sr2TiO4) samples doped with 2% of a mole of europium, praseodymium, and erbium were obtained using the solid-state synthesis method. The X-ray diffraction (XRD) technique confirms the phase purity of all samples and the lack of the influence of dopants at a given concentration on the structure of materials. The optical properties indicate, in the case of Sr2TiO4:Eu3+, two independent emission (PL) and excitation (PLE) spectra attributed to the Eu3+ ions at sites with different symmetries: low – excited at 360 nm and high – excited at 325 nm, while, for Sr2TiO4:Er3+ and Sr2TiO4:Pr3+, the emission spectra do not depend on the excitation wavelength. The measurements of X-ray photoemission spectroscopy (XPS) indicate the presence of only one type of charge compensation mechanism, which is based on the creation of strontium vacancies in all cases. This suggests that the different charge compensation mechanisms cannot easily explain the presence of Eu3+ at two non-equivalent crystal sites. The photocurrent excitation (PCE) spectroscopy investigations, that have not been reported in the literature so far, show that among all the studied dopants, only Pr3+ can promote the electrons to the conduction band and give rise to electron conductivity. The results collected from the PLE and PCE spectra allowed us to find the location of the ground states of lanthanides(II)/(III) in the studied matrix. [ABSTRACT FROM AUTHOR]

The conditions for the oxidation of Am(III) to Am(VI) and its reduction to Am(V) are shown, and the stability of these forms in a 0.1 M nitric acid model solution of the actinide-lanthanide fraction of high-level waste (HLW) containing isotopes of americium and curium and also praseodymium as a simulant of the behavior of fragmented lanthanides is defined. It was found that about 30% of americium in the Am(V) oxidation state of its initial content in a model solution containing a salting-out agent (ammonium nitrate) in an amount of 8 M, passes into the organic phase in one stage of extraction with a 30% solution of tributyl phosphate in Isopar-M. In this case, Cm and Pr are extracted by 80–85%. The distribution coefficient of Am was about 0.1, of Cm and Pr, about 1, and the separation factor of Am from Cm and Pr was about 10. Thus, the possibility of selective separation of americium from HLW for its subsequent transmutation in fast reactors was demonstrated. [ABSTRACT FROM AUTHOR]

The invention of superconductivity was a major advance of solid state physics. In the present review, we briefly discuss the emergence of RBa2Cu3O7–δ (R are lanthanides). In the first part, we consider the impact of lanthanide doping and the intricacy of the praseodymium anomaly. In the second part, we discuss the impact of external parameters such as pressure and electron irradiation on the critical superconducting parameters. This brief review concludes with future perspectives of the field, considering recent advances. [ABSTRACT FROM AUTHOR]

In this work, we present the operation of a femtosecond-laser-written diode-pumped visible waveguide laser based on praseodymium-doped lithium lutetium fluoride. The refractive index modification induced by the femtosecond laser in the crystal exhibits an anisotropic behavior, thus enabling the fabrication of different types of waveguides from single-track structures to stress-induced waveguides and depressed cladding structures. All the waveguides were characterized by realizing transmission measurements and the waveguide design was optimized to obtain extremely low propagation losses, equal to 0.12 d B / c m. Lasing has been achieved at 604 n m and 721 n m from different waveguides. In addition, stable continuous-wave lasing at 698 n m has been obtained in a depressed cladding waveguide. This wavelength corresponds to the one needed for the transition of the atomic clock based on the neutral strontium atom. In the end, we report the observation of laser emission at 645 n m from a depressed cladding waveguide. [ABSTRACT FROM AUTHOR]

Waste Electrical and Electronic Equipment (WEEE) that contains neodymium magnets (NdFeB) has the potential to serve as a valuable source of elements, including critical ones. These magnets contain Rare Earth Elements (REEs) like Neodymium, Dysprosium, and Praseodymium. A noteworthy method of recycling REEs involves the magnet-to-magnet process, wherein the NdFeB alloy is separated from WEEE and directly reused in the production of new products, specifically new NdFeB magnets. The initial step in this recycling process involves disintegration, a procedure aimed at reducing and segregating the materials within the WEEE. The conventional process of disintegrating WEEE for recycling faces challenges due to the presence of magnetic materials, making it ineffective with existing equipment. To address this, a specialized device called a disintegrator, using counter-rotating cutting shafts, has been developed for efficient shredding of WEEE containing NdFeB. The goal of the research is to develop a prototype shredder to effectively recover valuable metals, including REEs, from WEEE. Specific sub-objectives include motor and gearbox selection, shaft bearings selection, gear design, and cutting blades design. The work involved calculations and 3D modelling of the disintegrator components using Autodesk Inventor 2020 software. [ABSTRACT FROM AUTHOR]

"Neodymium and Praseodymium Doped Perovskite Materials for Highly Stable CuInS2‐Hole‐Transport Layer‐Based Perovskite Solar Cells" by R. Taheri‐Ledari, S. Gharibi, A. Maleki, S. Akin, and A.E. Shalan Energy Technol., 2022, 2100936. The above article, published online on 15 December 2021 in Wiley Online Library, has been retracted by agreement between the former journal Editor in Chief John Uhlrich, the interim Editor in Chief Till von Graberg, and Wiley‐VCH GmbH. Data irregularities in Figures 2b and 5b were pointed out by authors S. Akin, A. E. Shalan and corroborated by peer review from a specialist in the experimental technique. The authors were unable to provide the complete original data to restore confidence in these results. The retraction was necessary as the validity of the conclusions is substantially affected by these irregularities. While S.A. and A.E.S. agreed with the decision to retract the manuscript, R.T.L., A.M., and S.G. did not. Author contributions: R.T.L: Wrote the manuscript and interpreted the analyses. He has also drawn the graphics used in the manuscript. S.G: Performed all practical stages and provided the analyses. A.M: Managed all stages of the work, and financially supported the expenditures (Supervisor). S.A: Revised the manuscript and addressed the reviewers' comments. A.E.S: Edited the manuscript and improved the English presentation. [ABSTRACT FROM AUTHOR]

When investigating complex atomic spectra, it may happen accidentally that two or even several transitions between different pairs of combining energy levels have nearly the same wavenumber, and the observed spectral lines are overlapping (blend situations). In such cases, investigations of hyperfine structures can be very helpful in the identification of the involved transitions. In this paper, two complicated blend situations within the spectra of lanthanide atoms (Praseodymium and Lanthanum) are discussed as examples. The experimental methods applied are optogalvanic and laser-induced fluorescence spectroscopy, combined with emission spectra gained via Fourier transform spectroscopy. It is shown that, in such cases, a combination of optogalvanic and laser-induced fluorescence detection is necessary to find all transitions contributing to the observed spectral signatures.

Bismuth ferrite (BiFeO3) is an interesting multiferroic material due to its ferroelectric properties at room temperature. In this study, Bi1−x PrxFeO3 and BiFeO3 films were grown on quartz substrates by the chemical solution deposition method at 600oC of annealing temperature. Variation in molar concentration in Bi1−x PrxFeO3 was set (x = 0.03, 0.05, 0.1, and 0.2) to investigate their crystal structure and optical characteristics. BiFeO3 and Bi1−x PrxFeO3 films were examined using X-ray diffraction (XRD) and ultraviolet (UV)-vis spectrophotometer. The XRD results demonstrated that the addition of Pr in BiFeO3 shifted the diffraction angle to smaller angles so that it reduced their lattice constant. Besides, the crystal size declined with more Pr numbers, while the lattice strain expanded. The UV-vis characteristics of the films were measured in the wavelength range of 200–800 nm. The transmittance values of the Pr-doped BiFeO3 increased. Because of Pr doping, the refractive index of the Bi1−x PrxFeO3 films decreased while the energy dispersion increased.

Unveiling the structural evolution of single-crystalline compounds based on certain building units may help greatly in guiding the design of complex structures. Herein, a series of praseodymium antimony oxohalide crystals have been isolated under solvothermal conditions via adjusting the solvents used, that is, [HN(CH2CH3)3][FeII(2,2′-bpy)3][Pr4Sb12O18Cl15]·EtOH (1) (2,2′-bpy = 2,2′-bipyridine), [HN(CH2CH3)3][FeII(2,2′-bpy)3]2[Pr4Sb12O18Cl14)2Cl]·N(CH2CH3)3·2H2O (2), and (H3O)[Pr4Sb12O18Cl12.5(TEOA)0.5]·2.5EtOH (3) (TEOA = mono-deprotonated triethanolamine anion). Single-crystal X-ray diffraction analysis revealed that all the three structures feature an anionic zig-zag chain of [Pr4Sb12O18Cl15−x]n as the tertiary building unit (TBU), which is formed by interconnections of praseodymium antimony oxochloride clusters (denoted as {Pr4Sb12}) as secondary building units. Interestingly, different arrangements or linkages of chain-like TBUs result in one-dimensional, two-dimensional layered, and three-dimensional structures of 1, 2, and 3, respectively, thus demonstrating clearly the structural evolution of metal oxohalide crystals. The title compounds have been characterized by elemental analysis, powder X-ray diffraction, thermogravimetric analysis, and UV-Vis spectroscopy, and the photodegradation for methyl blue in an aqueous solution of compound 1 has been preliminarily studied. This work offers a way to deeply understand the assembly process of intricate lanthanide-antimony(III) oxohalide structures at the atomic level. [ABSTRACT FROM AUTHOR]

In the twenty-first century, mobile phones have become one of the most indispensable electronic products in the international community. The pollution of wasted mobile phones has become an urgent problem worldwide and needs special attention. In this paper, we applied the consumption and usage method to calculate the high-tech mineral elements in China from 2001 to 2019. To analyze the spatial distribution of per capita high-tech minerals in China, we proposed a model (3D GHM) through which a 3D grid of high-tech minerals in wasted mobile phones can be obtained in 1 km resolution. The results showed that the total amount of wasted mobile phones in China from 2001 to 2019 was 8.6 billion, with a growth rate of 1026.7% in 2019 compared with 2001. Moreover, the spatiotemporal distribution of wasted mobile phones is characterized by more in the east and less in the west. The total amount of cobalt, palladium, antimony, beryllium, neodymium, praseodymium, and platinum in wasted mobile phones from 2001 to 2019 reached 42,422.4 tons. Based on our results, we proposed a system for efficient collecting and recycling of wasted mobile phones in China. [ABSTRACT FROM AUTHOR]

Reduced glutathione (GSH) is a biologically important component that plays a critical role in antioxidant activity. Praseodymium(III) complex with GSH was synthesized and the complex formed was characterized by FTIR, XRD, TGA and SEM analysis. Infrared studies provided information on the mode of complexation between the lanthanide metal ion and GSH. XRD and TEM analysis showed the nanocrystalline phase and irregular morphology of the complex. TGA thermogram indicated good thermal stability of the complex. The in vitro antioxidant and antibacterial properties of the complex were studied. The results suggest that the praseodymium(III) complex possesses antioxidant and antibacterial activity. [ABSTRACT FROM AUTHOR]

Using X-ray diffraction phase and structural analysis and partially microstructural analysis methods the phase equilibria in the ternary system Pr–Cu–Ge were investigated and the isothermal sections of the phase diagram of the system at 870 K (0–50 at.% of Pr) and 670 K (50–100 at.% of Pr) were constructed. The existence of seven ternary compounds PrCu2Ge2, Pr2CuGe6, Pr2Cu3Ge3, PrCu0.817Ge2, Pr6Cu8Ge8, PrCu1.25–0.95Ge0.75–1.05, PrCu0.77–0.5Ge1.23–1.5 was established at 870 K. Only one ternary germanide ~ Pr0.6Cu0.22Ge0.18 with undetermined crystal structure was found in R rich range at 670 K. All ternary germanides are formed at constant composition except phases with AlB2 structure type. Appreciable solubility of the third component in the compounds of binary systems was not observed. The structure parameters were determined for ternary germanides: Pr2CuGe6 (structure type (ST) Ce2CuGe6, Pearson symbol (PS) oS18, space group (SG) Amm2, a = 4.19300(4) Å, b = 4.05742(4) Å, c = 21.4823(2) Å, RI = 0.0686, RP = 0.0993), PrCu1.25Ge0.75 (ST AlB2, PS hP3, SG P6/mmm, a = 4.2922(2) Å, c = 3.9193(3) Å, RI = 0.0543, RP = 0.1036), PrCu0.72Ge1.28 (ST AlB2, PS hP3, SG P6/mmm, a = 4.19347(6) Å, c = 4.1817(1) Å, RI = 0.0504, RP = 0.0728). Relationships of investigated system Pr–Cu–Ge with previously studied R–Cu–Ge systems, and structure peculiarities of established ternary germanides of Cu and Pr were analyzed. [ABSTRACT FROM AUTHOR]