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The frequency characteristics of impedance, phase difference between current and voltage, hodographs, and corresponding equivalent circuits of Fe nanofilms grown in a constant magnetic field on Gd2O3 and silicate glass substrates are investigated. It is shown that with increasing magnetic field strength from 40 E to 1200 E, the morphology of Fe films changes from labyrinthine to continuous, consisting of coalesced iron islands. This complex morphology of the films is the source of the induction and capacitance components of the imaginary part of the impedance. It was found that at a frequency of 630 Hz, a consistent electrical resonance is observed in Fe films, as well as a minimum value of the total impedance. At frequencies above 104 Hz, a sharp change in the impedance components and phase difference is observed in Fe films, which is probably due to the peculiarities of the film morphology. The Nyquist hodographs were constructed and the parameters of the corresponding equivalent circuits were calculated using the ZView computer program. It is shown that both the equivalent schemes of the hodographs and the peculiarities of the frequency dependence of the impedance and phase difference components depend largely on the morphology of the films, which is determined by the elasticity of the magnetic field applied during their growth, as well as by the chemical composition of the substrates. Gd2O3 substrates affect Fe films due to the d-f exchange interaction between the unfilled f and d electron shells of the atoms that make up the Gd2O3 and Fe layers. Silicate glass has an effect due to the ions of technological impurities contained in its composition, which can act as traps for electrons passing through the Fe film. [ABSTRACT FROM AUTHOR]

The simulation of fuel composition requires coupled calculations of neutron transport and burnup. It is generally assumed that the neutron flux density and cross-sections remain constant within a burnup step. However, when there are strong absorber poisons present, the reaction rates of the absorbers change too rapidly over time, necessitating extremely fine step sizes to ensure computational accuracy, which in turn leads to low computational efficiency. As a type of accident tolerant fuel (ATF), fully ceramic micro-encapsulated (FCM) fuel is a promising new type of nuclear fuel. Accelerated algorithms for burnup calculations of FCM fuel containing gadolinium isotopes have been developed based on the ALPHA code, including the projected predictor–corrector (PPC), the log-linear rate (LLR), and the high-order predictor–corrector (HOPC) methods (including CE/LI, CE/QI, LE/LI, and LE/QI). The performances of different algorithms under the two forms of Gd2O3 existence were analyzed. The numerical results show that the LE/QI method performs the best overall. For Gd2O3 existing in both forms, the LE/QI algorithm can maintain accuracy with a burnup step size of up to 1.0 GWd/tU, keeping the infinite multiplication factor kinf within 100 pcm, and it exhibits high accuracy in simulating the atomic number densities of Gd-155 and Gd-157 throughout the burnup process. [ABSTRACT FROM AUTHOR]

Yttrium and gadolinium oxides doped with Eu3+ ions were synthesized using the sol-gel method, which was assisted with oleic acid as a surface-directing agent. Their morphology and structure were characterized by X-ray diffraction and transmission electron microscopy. Yttrium oxide synthesized phosphors exhibited well-defined facets and good dispersion, while gadolinium oxide particles presented high coalescence. Moreover, all synthesized materials showed a cubic structure. A formation mechanism was proposed using the results of Fourier transform infrared spectroscopy, where the as-precipitated phosphors transformations from oxo-hydroxide to crystalline yttrium and gadolinium oxides were observed. In addition, a surface modification of particles was produced by the synthesis method. On the other hand, luminescence analyses showed a strong emission peak at 612 nm in both oxides, and it was found that gadolinium oxide was the most effective host for luminescence emission. This matrix required a smaller dopant content to reach its maximum luminescence emission and exhibited the highest theoretical quantum efficiency. Also, color purity was evaluated using the CIE 1931 coordinate system, where x coordinate was found to increase as a function of dopant content indicating a higher perception of red color for gadolinium oxide matrix. Finally, energy diagrams and rate equations were proposed to explain their energy transfer mechanisms. Highlights: Y2O3 and Gd2O3 attained carboxylate organic coatings on their surfaces. Effective solid solution of Eu3+ ion in Y2O3 and Gd2O3 hosts was determined by X-ray diffraction. Gd2O3 requires a smaller dopant content to reach maximum luminescence emission compared to Y2O3. Energy migration or f–f transition Eu3+→ Eu3+ is more important in Y2O3 matrix. [ABSTRACT FROM AUTHOR]

The present global energy crisis, along with the development of modern technologies, has compelled the scientists to search for smart materials, which possess the multifunctional properties simultaneously. Among such materials, bismuth-layered structure ferroelectrics (BLSFs) containing a perovskite structure have demonstrated the tendency to play a vital role. Herein, we report an engineered Gd 2 O 3 added Bi 3 TiTa 0·5 Nb 0·5 O 9 (BTTN) based material with composition Bi 3 TiTa 0·5 Nb 0·5 O 9 : x wt%Gd 2 O 3 (BTTN: x Gd) with x = 0–0.20 ceramics to investigate the ferroelectric, electric, piezoelectric and dielectric properties of the material. Highly dense (relative density of ∼96%) BTTN:0.15Gd has shown the best merits among all other compositions with improved remnant polarization (P r ∼ 7.86 μC/cm2), energy conversion efficiency (ƞ) of ∼63.48%, resistance of ∼2.2 × 1010 Ω and high piezoelectric co-efficient (d 33 ∼ 25 pC/N) at room temperature, which are much improved than pure BTTO or BTTN ceramics. Nonetheless, ceramic has shown the stable resistivity of ∼104 Ω at 500 °C, with a stable d 33 value of 22 pC/N (just 12% drop) after annealing at 600 °C. The ferroelectric to paraelectric phase transition of ceramic with the highest dielectric constant is reported at Curie temperature (T C) of 859 °C. Additionally, Density-Functional-Theory (DFT) and Density-Functional-Perturbation-Theory (DFPT) measurements are performed by employing generalized gradient approximation using the Quantum-ESPRESSO code. Structural, ferroelectric and electronic properties of BTTO, BTTN and Gd-added BTTN compounds are investigated. The calculated formation energies confirmed the thermodynamic stability of pseudo-tetragonal Gd-added BTTN compounds. Using the Berry-phase approach for piezoelectric materials, the calculated maximum polarization is 54.00 μC/cm2, which is in agreement with values obtained experimentally. Mentioned outcomes of the material clearly represent the potential of the BTTN:0.15Gd ceramic for the utilization in high-temperature piezoelectric devices. [ABSTRACT FROM AUTHOR]

Despite the significant Progression in nanocomposites (NCs) tailoring for ecological purposes, optimizing NCs for water treatment is still a challenge. Moreover, organic coloring (dyes) agents like Congo red (CR) and methylene blue (MB) were included which have carcinogenic effects. In this regard, photo-catalytic activity utilizing NCs for organic pollutants (dyes) removal is a great concern due to its viability and low cost. In this regard, a combination of nanocomposites including cerium Oxide (CeO 2), gadolinium oxide (Gd 2 O 3), and graphene oxide (GO) could be suggested. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) were utilized for characterization in addition to EDX, and electron microscopes (TEM, and FESEM). TEM micrograph exhibits TNC as scattered lanthanides oxides (CeO 2 , and Gd 2 O 3) grains upon GO sheets. It shows a clear decline in the average size to reach 25 nm for CeO 2 , and 40 nm for Gd 2 O 3. Also, FESEM reports that GO reduces the lanthanide oxides aggregation tendency in TNC, besides forming shallow pores within its rough surface. Regarding the thermal study, It is clear that activation energy (E*) is the almost equal enthalpy of activation (ΔH). It could refer to the presence of the tested composition at a higher degree of temperature (thermally stable). Nano-composite powders exhibited improvement in photo-catalytic efficiency and inhibition of photo-corrosion as compared with pure lanthanide oxides. The MB degradation potential of CeO 2 /Gd 2 O 3 /GO drops from 94.4 % in the first usage to 82.1 % in the fifth. [Display omitted] [ABSTRACT FROM AUTHOR]

The potential for amplifying tunnel magnetoresistance and magnetoimpedance in island nanofilms without energy consumption or the use of amplifying devices was studied. Such amplification was observed for the films deposited on a Gd2O3 layer instead of a glass substrate. The enhancement is due to the f–d exchange interaction established between atoms with unfilled f- and d-electron shells, present in both Fe and Gd2O3. The f–d exchange interaction enhances the ordering of the magnetic structure within the Fe ferromagnetic layer, increases its magnetization, and subsequently improves the properties that depend on this magnetization. Iron and Gd2O3 were selected because the magnetic moments of Fe in the iron group and Gd in the lanthanide series are among the highest effective ones: μFe = 7.13 μB and μGd = 7.95 μB. This, according to theory, determines the high energy of the f–d exchange interaction. The island morphology of Fe films deposited on a Gd2O3 layer enabled electron tunneling under the influence of the f–d exchange interaction. This allowed the study of tunnel magnetoresistance under direct current and magnetoimpedance under alternating current influenced by the f–d exchange interaction. The frequency dependence of the active component Z', the reactive component Z'', and the total impedance Z of Fe films on glass and Gd2O3 substrates, without and under a constant magnetic field of 7500 Oe, was analyzed. These characteristics are used to determine the frequency dependence of tunnel magnetoimpedance and estimate tunnel magnetoresistance for Fe island films on glass and Gd2O3 substrates. These characteristics were found to be 55 % higher, on average, for Fe deposited on Gd2O3 than for Fe on glass, both at a low frequency of 0.1 Hz for tunnel magnetoresistance and at higher frequencies of 1–105 Hz for tunnel magnetoimpedance. This results from the influence of f–d exchange interaction on electron tunneling between the iron islands. [ABSTRACT FROM AUTHOR]

The glass of composition 75B2O3-5Al2O3-15MgF2-(5-x)Li2O-xGd2O3 (with x = 0, 0.2, 0.4, 0.6) mole% was prepared using the fast melt-quenching technique, so as to investigate the manipulation of gadolinium oxide on the structure and spectroscopic properties of these compositions to be applicable in optoelectronic applications, which were investigated by different techniques. From vibrational investigation, it was revealed that the Gd2O3 influence on glass structure increased the non-bridging oxygen at the expense of BO3 groups. From spectroscopic investigation, as the incorporation of the Gd2O3 component increases in the oxyflouro structure, the energy band-gap property decreases, indicating an increase in the proportion of localized states formed near the conduction band for electrons. The band gap can be reduced as a result of the interaction between localized states and the conduction band. Moreover, ε′ and ε′′ rise with increased Gd2O3 content in the glass matrix and photon energy due to polarization. In addition to refractive index and optical conductivity, changing the phonon energy to a certain extent revealed that the prepared glass can be considered a fiber amplifier. [ABSTRACT FROM AUTHOR]

Two groups of Cherenkov glass detectors, containing six samples in total, have been produced in our laboratory with different compositions and configurations. The first group included three samples that were made of SiO2, and the other group contained three samples that were made of PbO+SiO2. All the samples were tested by using a PuBe source. Wavelength shifting (WLS) fibers were implemented in four samples (two from each group) to improve the light output of the Cherenkov detectors. Even though Cherenkov detectors have low noise due to the low-energy threshold and short decay constant (on the order of picoseconds), their light yield is low. A few hundred Cherenkov photons can be generated per mega-electron-volt. Without the WLS materials, most Cherenkov photons are likely to be absorbed within the glass sample before they can reach the photon sensor. WLS fibers do not directly increase the number of Cherenkov photons, but they can reduce the energy of Cherenkov photons and direct them toward the photon sensor. This photon energy reduction helps increase the efficiency of light collection and improves matching between photon wavelength and photon detector quantum efficiency. The objective of this work is to test Cherenkov glass detectors for the detection of neutrons by placing a 1-mm layer of Gd2O3 in front of the detectors. The focus is to increase the output light by observing the effect of the WLS fibers on the detection process with the use of different composition samples. The light output of the Cherenkov detectors was expected to increase more in the lead group than in the silicon group. Most of the Cherenkov energies are likely to be deposited within the glass sample. The approach is to direct the WLS photons to the photon sensor by allowing the energy deposition that takes place in the WLS fibers. A detailed model by Geant4 confirmed that the measured observations were reasonable. Both experimental and simulated results show an increase in light output when WLS fibers are added to the detectors. [ABSTRACT FROM AUTHOR]

Xinlin Li,1,2,* Baojuan Yang,3,4,* Mengfei Xu,1,2 Fangyi Li,3,4 Zhaoli Geng,1,2 Weiqiang Cui,3,4 Xingfu Sun,3,4 Yanle Li,3,4 Yi Liu1,2 1Department of Orthodontics, School and Hospital of Stomatology, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, People’s Republic of China; 2Shandong Key Laboratory of Oral Tissue Regeneration, Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, Shandong Provincial Clinical Research Center for Oral Diseases, Jinan, Shandong, 250012, People’s Republic of China; 3Key Laboratory of High Efficiency and Clean Mechanical Manufacture, Ministry of Education, School of Mechanical Engineering, Shandong University, Jinan, 250061, People’s Republic of China; 4National Demonstration Center for Experimental Mechanical Engineering Education, Shandong University, Jinan, 250061, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yi Liu, Department of Orthodontics, School and Hospital of Stomatology, Cheeloo College of Medicine, Shandong University, No. 44-1 Wenhua Road West, Jinan, Shandong, 250012, People’s Republic of China, Tel +86-531-88381630, Email yiliu@sdu.edu.cn Yanle Li, Key Laboratory of High Efficiency and Clean Mechanical Manufacture, Ministry of Education, Shandong University School of Mechanical Engineering, No. 17923, Jingshi Road, Jinan, 250061, People’s Republic of China, Tel +86-531-88392208, Email yanle.li@sdu.edu.cnIntroduction: The lack of osteoinductive, angiogenic and antimicrobial properties of hydroxyapatite coatings (HA) on titanium surfaces severely limits their use in orthopedic and dental implants. Therefore, we doped SiO2, Gd2O3 and CeO2 nanoparticles into HA to fabricate a HASiGdCe coating with a combination of decent antibacterial, angiogenic and osteogenic properties by the plasma spraying technique.Methods: The HASiGdCe coating was analyzed by SEM (EDS), surface roughness tests, contact angle tests, XRD, FTIR spectroscopy, tensile tests and electrochemical dynamic polarization tests. Methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa (PAO-1) were used as representative bacteria to verify the antibacterial properties of the HASiGdCe coating. We evaluated the cytocompatibility and in vitro osteoinductivity of the HASiGdCe coating by investigating its effect on the cell viability and osteogenic differentiation of MC3T3-E1 cells. We assessed the in vitro angiogenic activity of the HASiGdCe coating by migration assay, tube formation assay, and RT‒PCR analysis of angiogenic genes in HUVECs. Finally, we used infected animal femur models to investigate the biosafety, antimicrobial and osteointegration properties of the HASiGdCe coating in vivo.Results: Through various characterization experiments, we demonstrated that the HASiGdCe coating has suitable microscopic morphology, physical phase characteristics, bonding strength and bioactivity to meet the coating criteria for orthopedic implants. The HASiGdCe coating can release Gd3+ and Ce4+, showing strong antibacterial properties against MRSA and PAO-1. The HASiGdCe coating has been shown to have superior osteogenic and angiogenic properties compared to the HA coating in in vitro cellular experiments. Animal implantation experiments have shown that the HASiGdCe coating also has excellent biosafety, antimicrobial and osteogenic properties in vivo.Conclusion: The HASiGdCe coating confers excellent antibacterial, angiogenic and osteogenic properties on titanium implants, which can effectively enhance implant osseointegration and prevent bacterial infections, and it accordingly has promising applications in the treatment of bone defects related to orthopedic and dental sciences.Graphical Abstract: Keywords: hydroxyapatite coatings, SiO2, Gd2O3, CeO2, osseointegration, antibacterial

The simulation of fuel composition requires coupled calculations of neutron transport and burnup. It is generally assumed that the neutron flux density and cross-sections remain constant within a burnup step. However, when there are strong absorber poisons present, the reaction rates of the absorbers change too rapidly over time, necessitating extremely fine step sizes to ensure computational accuracy, which in turn leads to low computational efficiency. As a type of accident tolerant fuel (ATF), fully ceramic micro-encapsulated (FCM) fuel is a promising new type of nuclear fuel. Accelerated algorithms for burnup calculations of FCM fuel containing gadolinium isotopes have been developed based on the ALPHA code, including the projected predictor–corrector (PPC), the log-linear rate (LLR), and the high-order predictor–corrector (HOPC) methods (including CE/LI, CE/QI, LE/LI, and LE/QI). The performances of different algorithms under the two forms of Gd2O3 existence were analyzed. The numerical results show that the LE/QI method performs the best overall. For Gd2O3 existing in both forms, the LE/QI algorithm can maintain accuracy with a burnup step size of up to 1.0 GWd/tU, keeping the infinite multiplication factor kinf within 100 pcm, and it exhibits high accuracy in simulating the atomic number densities of Gd-155 and Gd-157 throughout the burnup process.

Because of its high radioactivity, high corrosivity, high toxicity and high heat release rate, safe and proper disposal of high-level liquid waste (HLLW) has always been the focus of radioactive waste management. After more than half a century of development, vitrification technology is a relatively mature technology widely recognized around the world that can achieve industrial scale treatment of HLLW. In recent years, with the rapid development of nuclear power in China, a certain amount of HLLW will be produced after reprocessing of the spent fuel produced each year. In order to properly and safely treat the HLLW generated from spent fuel reprocessing of nuclear power plants (NPPs), this paper conducted a study on the influence of adding gadolinium oxide (0%, 2%, 4%, 6%, 8% and 10%) on the structure and chemical stability of the solidified borosilicate glass on the basis of containing 20% simulated 33 GW·d/tU HLLW for the borosilicate glass base glass with the molar ratio of SiO2∶B2O3∶Na2O=1∶0.23∶0.54. XRD analysis shows that the glass samples are in stable amorphous glass state. Raman and NMR (nuclear magnetic resonance) analysis results show that, with the increase of Gd2O3 addition, the Si—O bound Q2 and Q3 structures in the glass structure tend to move to the low frequency region, and the proportion of B—O bound Q3 (B) structure gradually increases after a slightly decrease, while the proportion of Q4 (B) structure gradually decreases after a lightly increase. The chemical stability results show that the chemical stability of the glass solidified body samples is significantly improved with the addition of Gd2O3 and the leaching amount of Si, B, Na in the glass solidified sample is markedly reduced.

In this work, we fabricated a new series of borosilicate glass doped with different concentrations of Gd 2 O 3. Then the glass samples were converted to glass ceramics using heat treatment at 500 °C for 2 h, and then the temperature was raised to 700 °C for 3 h. The X-ray diffraction (XRD) affirmed the amorphous nature of glass samples and the crystalline phase of glass-ceramic samples, which is related to SiO 2 (cristobalite). The Fourier transform infrared displayed many peaks related to functional groups for B 2 O 3 and SiO 2 , with a slight difference between glass and glass ceramic samples. The band gap (E g) for glass samples is 3.69, 3.64, 3.65, and 3.67 eV for BSTSGd0.5, BSTSGd1, BSTSGd1.5, and BSTSGd2, respectively. At the same time, the E g for glass ceramics is 3.61, 3.64, 3.64, and 3.64 eV for GCBSTSGd0.5, GCBSTSGd1, GCBSTSGd1.5, and GCBSTSGd2, respectively. The mechanical properties of glass samples align with packing density (V t) and compactness results, which indicated the superiority of BSTSGd1 glass samples over other glass systems. For example, the V t values are 0.674, 0.688, 0.683, and 0.680 for BSTSGd0.5, BSTSGD1, BSTSGd1.5, and BSTSGD2, respectively. On the other hand, we compared the linear attenuation coefficient (μ) between glass and glass ceramics which showed high compatibility due to the low difference in density for glass and glass ceramics. The μ values for BSTSGd0.5, BSTSGD1, BSTSGd1.5, and BSTSGD2 glasses at 0.600 are 0.088, 0.092, 0.093, and 0.095 cm−1, which showed enhancement when adding Gd 2 O 3 to the glass system. It can be concluded that adding Gd 2 O 3 slightly reduced the particle range for proton and alpha particles and enhanced the neutron and gamma shielding properties, which indicates the possibility of using the current samples in the radiation shielding field. [ABSTRACT FROM AUTHOR]

xGd2O3–5SrO–(23.5−x)CaO–26Na2O–2.8P2O5–42.7B2O3 glasses have been synthesized via the well-known melt quenching technique. Gd2O3 content was increased from 0 to 0.5 mol% in steps of 0.1 at the expense of CaO, in the chemical composition of these glasses. The optical band gap was obtained using UV–Vis spectroscopy. Based on the absorption spectra, the optical energy gap (Eg) is evaluated using the Davis–Mott relation. Eg values decrease from 3.176 to 2.92 eV and from 3.55 to 3.43 eV for indirect and direct band gaps, respectively, with the incorporation of Gd2O3. Several optical properties, such as refractive index, optical basicity, dielectric constant, and molar polarization, have been calculated for every glass composition to interpret the experimental data. The refractive index was enhanced with the addition of Gd ions. The absorption edge was shifted toward the higher wavelength side from 366 to 383.66 nm by incorporating Gd2O3. The radiation shielding properties of the synthesized samples were calculated using the Phy-X/PSD program in the energy interval 0.015–15 MeV. The results showed that increasing Gd2O3 content increases mass and linear attenuation coefficients ( μ m and μ ), whereas the half-value layer (HVL) decreases. This glass system suits shielding and optical applications based on the obtained results. [ABSTRACT FROM AUTHOR]

xGd2O3–5SrO–(23.5−x)CaO–26Na2O–2.8P2O5–42.7B2O3 glasses have been synthesized via the well-known melt quenching technique. Gd2O3 content was increased from 0 to 0.5 mol% in steps of 0.1 at the expense of CaO, in the chemical composition of these glasses. The optical band gap was obtained using UV–Vis spectroscopy. Based on the absorption spectra, the optical energy gap (Eg) is evaluated using the Davis–Mott relation. Eg values decrease from 3.176 to 2.92 eV and from 3.55 to 3.43 eV for indirect and direct band gaps, respectively, with the incorporation of Gd2O3. Several optical properties, such as refractive index, optical basicity, dielectric constant, and molar polarization, have been calculated for every glass composition to interpret the experimental data. The refractive index was enhanced with the addition of Gd ions. The absorption edge was shifted toward the higher wavelength side from 366 to 383.66 nm by incorporating Gd2O3. The radiation shielding properties of the synthesized samples were calculated using the Phy-X/PSD program in the energy interval 0.015–15 MeV. The results showed that increasing Gd2O3 content increases mass and linear attenuation coefficients ( μ m and μ ), whereas the half-value layer (HVL) decreases. This glass system suits shielding and optical applications based on the obtained results. [ABSTRACT FROM AUTHOR]

Incorporating metal oxide nanoparticles into cement-based composites delays the hydration process and strength gain of cementitious composites. This study presents an approach toward improving the performance of bismuth oxide (Bi2O3) and gadolinium oxide (Gd2O3) particles in cementitious systems by synthesizing core–shell structures via a sol-gel process. Two types of silica coatings on cementitious pastes with 5% and 10% substitution levels were proposed. The rheology, hydration, and mechanical properties of the pastes were analyzed to determine the relationship between the coating type and nanoparticle concentration. The results indicate that despite the significant disparities in the performance of the resulting material, both methods are appropriate for cement technology applications. Bi2O3's silica coatings accelerate the hydration process, leading to early strength development in the cement paste. However, due to the coarse particle size of Gd2O3, silica coatings exhibited negligible effects on the early age characteristics of cement pastes. [ABSTRACT FROM AUTHOR]

A basic calcination process in one step was employed to create g-C3N4 photocatalytic composites modified by Gd2O3 nanoparticles. SEM (scanning electron microscopy), FTIR (Fourier-transform infrared spectroscopy), XRD (X-ray diffraction), EIS (electrochemical impedance spectroscopy), PL (photoluminescence studies) as well as TEM (transmission electron microscopy), XPS (X-ray photoelectron spectroscopy), and CV (cyclic voltammetry) were employed to explain the structural traits, optical properties, and morphological features of the processed photocatalyst. The findings show that Gd2O3 (Gd) does not affect the sample's crystalline structure but rather increases g-C3N4 surface area by spreading it superficially. Furthermore, Gd can redshift the light absorption peak, reduce the energy gap, and improve the efficiency with which photogenerated holes and electrons are removed in g-C3N4. The surface morphology of g-C3N4, in particular, could be significantly enhanced. We similarly employed three distinct photocatalytic complexes of Gd2O3 and g-C3N4 in 1:1, 2:1, and 3:1 proportions to degrade methylene blue (MB). After 100 min in visible light (400–800 nm), the photodegradation rate of composites is 58.8% for 1:1 (GG1), 94.5% for 2:1 (GG2), and 92% for 3:1 (GG3). In addition to the MB dye, the photocatalytic activity of synthesized materials was also studied for methyl orange. The result shows phenomenal degradation values, i.e.; for GG1 86%, GG2 96%, and for GG3 84.6%. The narrow band gap that separates the photogenerated electron and hole enhances g-C3N4 ability to degrade photo-catalytically. From the result, we concluded that the photocurrent and cyclic photocatalytic degradation of methylene blue shows that a composition of 2:1 Gd2O3/g-C3N4 has high photocatalytic stability. [ABSTRACT FROM AUTHOR]

Efficient cleaning of contaminated water by photocatalysis has become an effective strategy in recent years due to its environmental and ecological designation. Cadmium sulfate (CdS) is an excellent photocatalyst in the visible region but has low quantum efficiency. In order to increase the photocatalytic efficiency, CdS was modified with gadolinium oxide (Gd2O3) and combined with graphene oxide (GO) nanoparticles. The estimated crystallite size (Ds) for Gd2O3, CdS/Gd2O3, and CdS/Gd2O3@GO was 29.6, 11.6, and 11.5 nm, respectively. The degradation of methylene blue (MB) reaches the highest values after 60 min under visible light irradiation with a dye concentration of (0.25 ppm). Whereas in powdered composition the efficiency of dye removal has been enhanced under UV irradiation, it reduced by increasing the MB concentration to 0.50 ppm with visible light irradiation. In addition, the CdS with/without Gd2O3 and GO were integrated into electrospun nanofibrous cellulose acetate (CA) through the electrospinning technique. The compounds of Gd2O3, CdS/Gd2O3, and CdS/Gd2O3/GO were encapsulated into CA nanofibers for the degradation of MB under visible and UV irradiation. The apparent rate constant (k) achieves a value of 0.006, 0.007, and 0.0013 min−1 while the removal efficiency reaches 41.02%, 54.71%, and 71.42% for Gd2O3@CA, CdS/Gd2O3@CA, and CdS/Gd2O3/GO@CA, respectively, after 60 min under UV irradiation. [ABSTRACT FROM AUTHOR]

Various concentrations of europium-doped gadolinium oxide powders are synthesized by a high-temperature solid-state reaction method. Raman spectra of the compounds exhibited the vibrations and symmetry of monoclinic single-phase crystal formation, with the predominant monoclinic phase of Gd2O3 which is consistent with the XRD findings reported earlier. The core level electron emission spectra revealed the formation of highly valence-stable compound systems with shell structures corresponding to Eu3+ and Gd3+ electronic states. In-depth analysis of photoluminescence spectra with multiple emissions in the yellow–red region corresponding to transitions of 5D0–7F2, 5D0–7F1, and 5D0–7F0 which arise due to europium substitution brought out interesting findings of colourinescence parameters. Investigations of Judd–Ofelt parameters, mean lifetimes, radiative transition rates, and CIE coordinates revealed the compatibility of the prepared samples as the good orange-red emitter. [ABSTRACT FROM AUTHOR]

The relationship between internal mechanical stresses, surface morphology, nanoscale electrical properties, and optical characteristics in TiO2, Gd2O3, Er2O3, and SiO2 thin films on SiC substrates was investigated. The oxide films were synthesized using the rapid thermal annealing and analyzed through scanning spreading resistance microscopy, photoluminescence, and absorption spectroscopy. Tensile stresses were found in the films, they are attributed to thermal and lattice mismatch, oxidation, and grain boundaries. These stresses influence on surface morphology, resistivity variations, and photoluminescence intensity. Surface roughness and grain structure were found to correlate with variations in resistivity, which were attributed to conductive pathways along grain boundaries and possible metallic phases. Photoluminescence intensity was also observed to correlate with estimated lattice mismatch strain. Gd2O3/SiC exhibited the fewest defects, while Er2O3 and TiO2 showed more, with Er2O3 being the most mismatched and roughest. The results indicate that internal strains in oxide thin films on SiC substrates can influence on surface morphology, leading to formation of defects and spatial inhomogeneity. These fluctuations in local conductivity and luminescence center density have significant implications for dielectric and optical applications. The study provides insights for future processing refinements to mitigate internal strains and enhance the performance of oxide thin films in semiconductor and optical technologies. [ABSTRACT FROM AUTHOR]

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This study reports on the fabrication and characterization of luminescent aerogels of Gd2O3:Eu3+ and Gd2O3:(Eu3+, Tb3+), synthetized by the sol–gel method and the supercritical drying technique. The mol% concentration of the Eu3+ and Tb3+ ions in the synthesis were varied to study the effects of concentration on the luminescent properties of the aerogels. The results show that the Gd2O3:Eu3+ and the Gd2O3:(Eu3+, Tb3+) aerogels exhibited a maximum emission at λ = 613 nm. For all the samples, a decay in light intensity occurred when a concentration of 8 mol% of Eu3+ was exceeded, regardless of whether the Tb3+ ion was present. The analysis by X-ray diffraction showed that the aerogels of Gd2O3:Eu3+, like those of Gd2O3:(Eu3+, Tb3+), had a cubic crystalline structure with no change even at high concentrations of Eu3+. The microscopy analyses showed that the aerogels present a porous structure made up of interconnected quasi-spherical nanoparticles that formed a three-dimensional network. Quantum yield analysis shows that Tb3+ acts as a sensitizer of Eu3+, increasing the light intensity in the aerogels. The results reveal that it is possible to manufacture luminescent aerogels of rare-earth oxides that can be used in opto-electronic devices. [ABSTRACT FROM AUTHOR]

This study reports on the fabrication and characterization of luminescent aerogels of Gd2O3:Eu3+ and Gd2O3:(Eu3+, Tb3+), synthetized by the sol–gel method and the supercritical drying technique. The mol% concentration of the Eu3+ and Tb3+ ions in the synthesis were varied to study the effects of concentration on the luminescent properties of the aerogels. The results show that the Gd2O3:Eu3+ and the Gd2O3:(Eu3+, Tb3+) aerogels exhibited a maximum emission at λ = 613 nm. For all the samples, a decay in light intensity occurred when a concentration of 8 mol% of Eu3+ was exceeded, regardless of whether the Tb3+ ion was present. The analysis by X-ray diffraction showed that the aerogels of Gd2O3:Eu3+, like those of Gd2O3:(Eu3+, Tb3+), had a cubic crystalline structure with no change even at high concentrations of Eu3+. The microscopy analyses showed that the aerogels present a porous structure made up of interconnected quasi-spherical nanoparticles that formed a three-dimensional network. Quantum yield analysis shows that Tb3+ acts as a sensitizer of Eu3+, increasing the light intensity in the aerogels. The results reveal that it is possible to manufacture luminescent aerogels of rare-earth oxides that can be used in opto-electronic devices. [ABSTRACT FROM AUTHOR]

The acetone gas sensor is one type of sensor being researched for its application because it detects the presence of diabetes in sufferers. Gas sensors with high sensitivity and low operating temperature have been extensively investigated for this purpose, and this research is focused on the same purpose. Synthetization and characterization of LaFeO3 with co-doping Gd2O3 and CoO thick film ceramics for acetone gas sensor was conducted. LaFeO3 was made using the co-precipitation method with 2.5% CoO for each and 0%, 2.5%, and 5% Gd2O3 variation to the LaFeO3. The LaFeO3 thick film was prepared using the screen-printing technique and calcined at 800°C for two hours. The analysis of crystal structure characterization using X-Ray Diffraction (XRD) resulted in LaFeO3 with co-doping Gd2O3 and CoO thick film ceramics having the same cubic crystal phase with smaller lattice parameters and crystallite sizes after doping were added. The results of morphology structure characterization using Scanning Electron Microscopy (SEM) showed the grain size of the LaFeO3 with co-doping 2.5% CoO and 0%, 2.5%, and 5% Gd2O3 samples to support the analysis of electric property characterization later on. The electric property characterization showed that LaFeO3 with various Gd2O3 concentrations, as part of co-doping with 2.5% CoO, resulted in higher sensitivity compared to the lacking of Gd2O3 one. In order, the maximum sensitivity values of each Gd2O3 concentration are 2.74, 3.06, and 8.76 when exposed to 270 ppm acetone gas at 310°C. Gd2O3, as part of co-doping in LaFeO3 with CoO 2.5%, has successfully increased the sensitivity to the gas sensor yet still can not meet the expectation towards the operating temperature, which is still high compared to other references.

In this paper, two dielectric layers of Al2O3 and Gd2O3 were prepared by an atomic layer deposition (ALD) and magnetron sputtering deposition (SD), respectively. Based on this, a metal-oxide-semiconductor field-effect transistor (MOSFET) was successfully prepared on a hydrogen-terminated single-crystal diamond (H-diamond), and its related properties were studied. The results showed that this device had typical p-type channel MOSFET output and transfer characteristics. In addition, the maximum current was 15.3 mA/mm, and the dielectric constant of Gd2O3 was 24.8. The effective mobility of MOSFET with Gd2O3/Al2O3 was evaluated to be 182.1 cm2/Vs. To the best of our knowledge, the bilayer dielectric of Gd2O3/Al2O3 was first used in a hydrogen-terminated diamond MOSFET and had the potential for application. [ABSTRACT FROM AUTHOR]

Rare earth oxides such as La2O3 and Gd2O3 are abundant in waste optical glass. The separation of rare earth oxides is beneficial to the recycling of rare earth resources. In this study, the rare earth oxide Gd2O3 particles were separated from La2O3 particles using high gradient magnetic separation, and the influence of different fluid media (i.e., water, anhydrous ethanol, and their mixture) on the separation results was investigated. By using the measured zeta potential of oxide particles in water/ethanol of different pH and water with different dispersants (Na2SiO3 9H2O, citric acid, Na2CO3, and sodium hexametaphosphate), the DLVO (Derjaguin–Landau–Verwey–Overbeek) potential calculations and their analysis applied to high gradient magnetic separation results were also performed. The results showed that using anhydrous ethanol or adding a dispersant in water as a fluid medium can promote the separation of magnetic Gd2O3 particles under a high-gradient magnetic field. Among the different conditions, anhydrous ethanol can improve the grade of Gd2O3 to 95% from 70% with water. Furthermore, ethanol can be reused after filtration, making it an environmentally friendly fluid medium. Among the four dispersants, sodium hexametaphosphate, Na2SiO3, and Na2CO3 can also increase the separation rate of La2O3 and Gd2O3 to about 95%. The effect of citric acid on the separation performance is slightly worse, and the recovery rate of Gd2O3 is 80%. This study provides a new reference for selecting a fluid medium for magnetic separation. [ABSTRACT FROM AUTHOR]

In this work, pure gadolinium oxide (Gd2O3) and mixed gadolinium oxide (Gd2O3)–magnesium oxide (MgO) composites were synthesized by simple hydrothermal method and calcination treatment. Two kinds of materials were used to remove uranyl ions from aqueous solution and characterized the structure and morphology by means of XRD, FT-IR, SEM, EDS and XPS. MgO was introduced into Gd2O3 material, which effectively avoided the agglomeration of Gd2O3 material and increased the adsorption capacity. The effects of different initial pH, initial uranium concentration and contact time on the adsorption performance of UO22+ were investigated by static adsorption experiments. At 25 °C, the maximum adsorption capacities of Gd2O3 and Gd2O3–MgO for UO22+ were 473.43 mg·g−1 and 812.41 mg·g−1, respectively. The adsorption process was fitted well with the Langmuir isotherm model and pseudo-second-order kinetic model. The thermodynamic fitting parameters (ΔG < 0, ΔS > 0 and ΔH > 0) indicated that the adsorption properties are endothermic and spontaneous. Gd2O3–MgO has a relatively large specific surface area and high adsorption capacity, but its stability and regeneration ability are reduced after three times of reuse. The possible adsorption mechanism is derived from XPS and FT-IR analysis, which mainly involves the complexation of –OH and U(VI) generated by the hydration on the surface of the materials. [ABSTRACT FROM AUTHOR]

Ion irradiation induced phase transformations in Gd 2 O 3 nanorods dispersed on TEM grids, are investigated using synchrotron X-ray diffraction and transmission electron microscopy. Ion irradiation induced cubic (C) to monoclinic (B) phase transformation is observed in Gd 2 O 3 nanorods. Gd 2 O 3 nanorods are partially transformed to monoclinic phase at 0.63 dpa (5 × 1016 ions/cm2) itself. The C→B phase transformation is reconstructive type transformation where the role of O-vacancies and diffusion are very important. During He+ ion irradiation, the displacement cascades produced O-vacancies and during the non-melting thermal spike regime, diffusion was assisted and it resulted in the phase transformation. In addition to phase transformation, TEM investigations shows formation of amorphous carbon layer around the nanorods and welding of the nanorods, upon ion irradiation. These observations are explained based on the mechanisms of GOLF (giant onion like fullerene) formation and the localized surface melting during thermal spike. • 100 keV He + ion induced cubic to monoclinic transformationobserved in Gd 2 O 3 nanorods. • O-vacancies produced by displacement cascades, and during the non-melting thermal spike regime, diffusion was assisted. • Vacancies and diffusion assists the C.→B phase transformation is reconstructive type phase transformation. • Synchrotron XRD is able to detect the small volume fraction of monoclinic phase. • The Gd 2 O 3 nanorods are found to be nanowelded upon ion irradiation. [ABSTRACT FROM AUTHOR]

This study discusses the effect of using 232Th instead of 238U on the neutronic characteristics and the main operating parameters of the pressurized water reactor (PWR). MCNPX version 2.7 was used to compare the neutronic characteristics of UO2 with (Th, 235U)O2 and (Th, 233U) O2. Firstly, the infinity multiplication factor (Kinf), thermal neutron flux, and power distribution have been studied for the investigated fuel types. Secondly, the effect of Gd2O3 and Er2O3 on the Kinf and on the radial thermal neutron flux and thermal power has been investigated to distinguish which of them is more suitable than the other in reactivity management. Thirdly, to illustrate the effectiveness of 232Th in decreasing the inventory of both the actinides and non-actinides, the concentration of plutonium (Pu) isotopes and minor actinides (MAs) has been simulated with the fuel burnup. Besides, due to their large thermal neutron absorption cross-section, the concentrations of 135Xe, 149Sm, and 151Sm with the fuel burnup have been investigated. Finally, the main safety parameters such as the reactivity worth of the control rods (ρCR), the effective delayed neutron fraction βeff, and the Doppler reactivity coefficient (DRC) were calculated to determine to which extent these fuel types achieve the acceptable limits.

The neutron- and X-ray-shielding, morphological, physical, mechanical, and self-healing properties were investigated for natural rubber (NR) composites containing varying gadolinium oxide (Gd2O3) contents (0, 25, 50, 75, and 100 parts per hundred parts of rubber; phr) to investigate their potential uses as self-healing and flexible neutron- and X-ray-shielding materials. Gd2O3 was selected as a radiation protective filler in this work due to its preferable properties of having relatively high neutron absorption cross-section (σabs), atomic number (Z), and density (ρ) that could potentially enhance interaction probabilities with incident radiation. The results indicated that the overall neutron-shielding and X-ray-shielding properties of the NR composites were enhanced with the addition of Gd2O3, as evidenced by considerable reductions in the half-value layer (HVL) values of the samples containing 100 phr Gd2O3 to just 1.9 mm and 1.3 mm for thermal neutrons and 60 kV X-rays, respectively. Furthermore, the results revealed that, with the increase in Gd2O3 content, the mean values (± standard deviations) of the tensile strength and elongation at break of the NR composites decreased, whereas the hardness (Shore A) increased, for which extreme values were found in the sample with 100 phr Gd2O3 (3.34 ± 0.26 MPa, 411 ± 9%, and 50 ± 1, respectively). In order to determine the self-healing properties of the NR composites, the surfaces of the cut samples were gently pressed together, and they remained in contact for 60 min; then, the self-healing properties (the recoverable strength and the %Recovery) of the self-healed samples were measured, which were in the ranges of 0.30–0.40 MPa and 3.7–9.4%, respectively, for all the samples. These findings confirmed the ability to autonomously self-heal damaged surfaces through the generation of a reversible ionic supramolecular network. In summary, the outcomes from this work suggested that the developed Gd2O3/NR composites have great potential to be utilized as effective shielding materials, with additional dual shielding and self-healing capabilities that could prolong the lifetime of the materials, reduce the associated costs of repairing or replacing damaged equipment, and enhance the safety of all users and the public. [ABSTRACT FROM AUTHOR]

The current work aims to synthesize highly fluorescent and surface-functionalized gadolinium oxide nanoparticles (Gd2O3 NPs) with (3-mercaptopropyl) trimethoxysilane (MPTMS). The surface modification of Gd2O3 nanoparticles with MPTMS enhanced the stability and solubility of the nanoprobe in aqueous media. The size of the nanoprobe was controlled to 7 ± 1 nm using MPTMS coating. These valued points made the MPTMS@Gd2O3 nanoparticles as economical, highly sensitive, selective nanoprobe with a quick response time for the detection of cysteine via the simple fluorescence-based methodology. The proposed strategy has offered the reliable detection of cysteine in the concentration range of 1–100 µm with a detection limit of 42 nm. The selective sensing of cysteine in human serum has jointly acknowledged the potential prospect of developing sensors in body fluids with great accuracy. [ABSTRACT FROM AUTHOR]

Up-conversion Gd2O3:Er,Yb nanoparticles (NPs) were fabricated by laser ablation in liquid, and the effect of laser irradiation time on their characteristics was investigated. The light source (a focused 532 nm second harmonic laser beam generated from a Nd:YAG laser) was used to irradiate the target pellet in water for 5, 15, or 30 min. Coarse NPs (> 200 nm) and fine NPs (< 100 nm) were observed. It is believed that the angular-shaped NPs resulted from fragmentation, and the spherical NPs were formed by laser melting or laser ablation in liquid (especially the < 80 nm particles). The main primary particle size range (25–75%), for the samples that had been irradiated for 5 min, was approximately 30–94 nm; for 15 min: 11–21 nm; and for 30 min: 11–24 nm. The secondary particle size decreased from 1000 to 200 nm with increasing irradiation time. The photon number was 2.3 for all the irradiation times. In every case, the zeta potential was above 15 mV, indicating a relatively stable dispersion. The transparency of the NP suspensions was almost the same for both the 5 and 15 min laser irradiation times, and higher than that of the 30 min suspension. [ABSTRACT FROM AUTHOR]

Water pollution is one of the most significant threats for the present and future generation. Mostly, the water bodies are polluted by the industrial pollutants like rhodamine B (RhB) and methylene blue (MB). Examinations for the deprivation of RhB and MB dyes from the wastewater are crucial and were done in this article. In this study, the ZnO and Gd2O3 nanomaterials were synthesized by a two-step strategy of phytochemical-assisted green synthesis using the plant extract of Bryonia epigaea (Corallo carpus epigaeus). The synthesized nanomaterials were characterized for their optical absorbance properties and photoluminescence studies. The conducted XRD analysis confirmed that the particle obeyed the wurtzite structure with hexagonal phase. The FESEM analysis clearly indicated the rod-like structure of the ZnO nanomaterials and spherical shape of Gd2O3 nanomaterials. The degradation efficiency was remarkably higher for the ZnO/Gd2O3 nanocomposites which proved that the integration of Gd2O3 nanomaterials improved the catalytic activity of ZnO nanomaterials. [ABSTRACT FROM AUTHOR]

In this paper, two dielectric layers of Al2O3 and Gd2O3 were prepared by an atomic layer deposition (ALD) and magnetron sputtering deposition (SD), respectively. Based on this, a metal-oxide-semiconductor field-effect transistor (MOSFET) was successfully prepared on a hydrogen-terminated single-crystal diamond (H-diamond), and its related properties were studied. The results showed that this device had typical p-type channel MOSFET output and transfer characteristics. In addition, the maximum current was 15.3 mA/mm, and the dielectric constant of Gd2O3 was 24.8. The effective mobility of MOSFET with Gd2O3/Al2O3 was evaluated to be 182.1 cm2/Vs. To the best of our knowledge, the bilayer dielectric of Gd2O3/Al2O3 was first used in a hydrogen-terminated diamond MOSFET and had the potential for application.

Poly ɛ‐caprolactone (PCL) and poly lactic acid (PLA) stand out as biocompatible polymers. In this study, PCL and PLA were blended in 40:60 ratio, respectively, and then the Gd2O3 compound, which is an important earth element oxide, was mixed in PLA–PCL shape memory polymer (SMP) blend at different rates and polymer blend nanocomposites were obtained. First of all, the effects of Gd2O3 oxide on the thermal properties of the SMP blend were determined with a differential scanning calorimeter (DSC) and thermogravimetric analyzer (TGA), and it was determined that Gd2O3 did not have a significant effect on the melting temperature of the blend, while it significantly increased its thermal stability. As a result of the XRD (X‐ray diffraction) analysis of the composites at room temperature, it was determined that the semicrystalline blend, with the addition of Gd2O3, increased its crystalline property. When the shape memory effect was examined, it was understood that the additive did not eliminate the shape memory effect. When the magnetic property of the gadolinium oxide‐doped composite, which is magnetocaloric oxide, was examined, the magnetic property of the composite changed from diamagnetic to paramagnetic with increasing additives. Finally, the mechanical properties of the shape memory blend composite were investigated and no regular changes were observed in the mechanical properties with increasing Gd2O3. [ABSTRACT FROM AUTHOR]

Er3+/Yb3+ double doped Gd2O3 down-conversion luminescent materials were prepared by sol-gel method and the doping ratio of Yb3+ was adjusted according to the doping mole percentage n(Gd3+)∶n(Er3+)∶n(Yb3+)=100∶2∶x(x=0, 3, 6, 9). The effects of Er3+/Yb3+ double doping on the crystal structure, micro morphology, luminescence properties and quantum transfer efficiency of Gd2O3 luminescent materials were studied by XRD, SEM, fluorescence spectra and fluorescence attenuation. The results showed that the doping of Er3+/Yb3+ didn't change the crystal structure of Gd2O3, but caused a high angle shift of the characteristic diffraction peak of the sample. The grain size of all samples were about 65~85 nm, which belonged to nano materials. With the increase of Yb3+ doping, the diffraction peak intensity of the sample in the visible region and near-infrared region first increased and then decreased, and the diffraction peak intensity of Gd2O3 luminescent material with 2Er:3Yb doping ratio reached the maximum. With the increase of Yb3+ doping, the sample gradually shifted from yellow green light region to blue light region. The color transformation of Gd2O3 luminescent material could be realized by adjusting the doping ratio of Er3+/Yb3+. With the increase of Yb3+ doping, the average life of the sample decreased gradually, and the energy transfer efficiency and quantum efficiency increased gradually. The energy transfer efficiency and quantum efficiency of Gd2O3:2Er/9Yb were 77.80% and 177.80% respectively, which had high energy transfer efficiency and quantum efficiency. [ABSTRACT FROM AUTHOR]

A ternary nanocomposite (TNC) was fabricated for introducing multifunctional properties for various biomedical applications. The nanocomposites consist of hydroxyapatite (HAP) combined with/without graphene oxide (GO) and gadolinium oxide (Gd2O3). The lattice constants of HAP were around 9.4285 and 6.7476 Å, while for Gd2O3 was around 10.8441 Å. The morphological investigation detected the nanosheets of GO, and nanorods of HAP/Gd2O3 with length of 27 nm. Moreover, the topological study based on a field emission scanning electron microscope (FESEM) showed that HAP/GO had average roughness (Ra) of 4.8 nm, and the root mean square value (Rq) with a value of 7 nm. Furthermore, the average pore size reached 7.99 nm for the NC of HAP/GO. In addition, the cumulative surface area using the density functional theory (DFT) method was calculated at around 44.61 m2/g for TNC. The cell viability in vitro of osteoblast cell line improved from 95.6 ± 0.6% to 96.7 ± 0.5% which indicates the biocompatibility of the implants to be used in biomedical applications.

Rare earth oxides such as La2O3 and Gd2O3 are abundant in waste optical glass. The separation of rare earth oxides is beneficial to the recycling of rare earth resources. In this study, the rare earth oxide Gd2O3 particles were separated from La2O3 particles using high gradient magnetic separation, and the influence of different fluid media (i.e., water, anhydrous ethanol, and their mixture) on the separation results was investigated. By using the measured zeta potential of oxide particles in water/ethanol of different pH and water with different dispersants (Na2SiO3 9H2O, citric acid, Na2CO3, and sodium hexametaphosphate), the DLVO (Derjaguin–Landau–Verwey–Overbeek) potential calculations and their analysis applied to high gradient magnetic separation results were also performed. The results showed that using anhydrous ethanol or adding a dispersant in water as a fluid medium can promote the separation of magnetic Gd2O3 particles under a high-gradient magnetic field. Among the different conditions, anhydrous ethanol can improve the grade of Gd2O3 to 95% from 70% with water. Furthermore, ethanol can be reused after filtration, making it an environmentally friendly fluid medium. Among the four dispersants, sodium hexametaphosphate, Na2SiO3, and Na2CO3 can also increase the separation rate of La2O3 and Gd2O3 to about 95%. The effect of citric acid on the separation performance is slightly worse, and the recovery rate of Gd2O3 is 80%. This study provides a new reference for selecting a fluid medium for magnetic separation.

Gd2O3:Er,Yb upconversion nanoparticles were obtained by laser ablation in liquid, and their optical properties were investigated. These nanoparticles are suitable for photodynamic therapy which is a cancer treatment approach. Since the nanoparticles are for medical use, purity is required. Thus, laser ablation in liquid was selected as a suitable production method because it produces no impurities. Nanoparticles were prepared by Nd:YAG (532-nm) laser-irradiation to Gd2O3:Er,Yb target in water. The nanoparticles' compositions were analyzed using X-ray diffraction, which showed that the nanoparticles and target raw material have the same peak. The primary particle size was measured using scanning electron microscopy, which revealed the coarse (>100 nm) and fine (<100 nm) nanoparticles. The secondary particle size was investigated by dynamic light-scattering, which indicated the aggregation of fine nanoparticles. Upconversion luminescence and photon number were measured using a photoluminescence spectrometer with 980-nm laser excitation. Visible light was obtained due to upconversion. The photoluminescence intensity increased until the middle fluence and slightly decreased at the high fluence. Besides, the photon number was increased from 2.3 to 3.2. It is considered that nonradiative deactivation of fine nanoparticles affected the emission characteristics and photon number. [ABSTRACT FROM AUTHOR]

The neutron- and X-ray-shielding, morphological, physical, mechanical, and self-healing properties were investigated for natural rubber (NR) composites containing varying gadolinium oxide (Gd2O3) contents (0, 25, 50, 75, and 100 parts per hundred parts of rubber; phr) to investigate their potential uses as self-healing and flexible neutron- and X-ray-shielding materials. Gd2O3 was selected as a radiation protective filler in this work due to its preferable properties of having relatively high neutron absorption cross-section (σabs), atomic number (Z), and density (ρ) that could potentially enhance interaction probabilities with incident radiation. The results indicated that the overall neutron-shielding and X-ray-shielding properties of the NR composites were enhanced with the addition of Gd2O3, as evidenced by considerable reductions in the half-value layer (HVL) values of the samples containing 100 phr Gd2O3 to just 1.9 mm and 1.3 mm for thermal neutrons and 60 kV X-rays, respectively. Furthermore, the results revealed that, with the increase in Gd2O3 content, the mean values (± standard deviations) of the tensile strength and elongation at break of the NR composites decreased, whereas the hardness (Shore A) increased, for which extreme values were found in the sample with 100 phr Gd2O3 (3.34 ± 0.26 MPa, 411 ± 9%, and 50 ± 1, respectively). In order to determine the self-healing properties of the NR composites, the surfaces of the cut samples were gently pressed together, and they remained in contact for 60 min; then, the self-healing properties (the recoverable strength and the %Recovery) of the self-healed samples were measured, which were in the ranges of 0.30–0.40 MPa and 3.7–9.4%, respectively, for all the samples. These findings confirmed the ability to autonomously self-heal damaged surfaces through the generation of a reversible ionic supramolecular network. In summary, the outcomes from this work suggested that the developed Gd2O3/NR composites have great potential to be utilized as effective shielding materials, with additional dual shielding and self-healing capabilities that could prolong the lifetime of the materials, reduce the associated costs of repairing or replacing damaged equipment, and enhance the safety of all users and the public.

Gd 2 O 3 was added to increase the properties of corundum–mullite ceramic composites by enhancing the microstructural densification using coal-series kaolin and α-Al 2 O 3. The effect of Gd 2 O 3 addition on the microstructure and properties of ceramic composites was explored. The results showed that the formation of Gd 2 O 3 –Al 2 O 3 –SiO 2 liquid phase could improve the bending strength, hardness, and acid resistance, since such liquid phase promoted microstructural densification via a reaction between Gd 2 O 3 and Al 2 O 3 –SiO 2 binary system in this Al 2 O 3 -rich and SiO 2 -poor system. The precipitation of mullite and gadolinium disilicate during thermal shocks resulted in enhanced bending strength. In particular, sample AG5 (80 wt% Al 2 O 3 , 20 wt% coal-series kaolin, and 5 wt% additional Gd 2 O 3) sintered at 1550 °C was considered as candidate for heat transmission pipeline for the optimum comprehensive performance. [ABSTRACT FROM AUTHOR]