摘要：
Ruthenium removal from complex solutions (highly saline effluents, seawater) is a critical challenge. Herein, the sorption capacity of chitosan/SiO2 composite beads (Ch-Si) for ruthenium nitrosyl is increased three-fold after phosphoramidate grafting (DPA-Ch-Si, 1.6 mmol Ru g−1) at pH 5. Uptake kinetics and sorption isotherms are compared at pH0: 3, 5 and 10; playing with the mode of agitation (mechanical, MA, vs. ultrasonic treatment, UT). The sorbent maintains good sorption capacities at pH 3 and 10. Uptake kinetics modeled by pseudo-first order rate equation is boosted by functionalization. For Ch-Si, sorption isotherms are modeled by the Langmuir or Sips equations (depending on the pH), while for DPA-Ch-Si the best fits depend on pH, temperature and mode of agitation. Ruthenium sorption is spontaneous and endothermic for the two sorbents. For DPA-Ch-Si, the sorption capacity increases from 1.62 to 1.70 mmol Ru g−1 to 2.23–2.32 mmol Ru g−1 (T increasing from 21 to 50 °C). Nitric acid solution (0.3 M) reveals highly efficient for back extraction; ruthenium is completely released in <15 min. The functionalized sorbent can be reused for a minimum of 10 cycles, with limited loss in performance. Phosphoramidation improves sorption selectivity for the treatment of equimolar multicomponent solutions (Na, Ca, Mg, Fe, Al, U, and Nd). The effect of pH on sorption selectivity is evaluated in simple multi-metal solutions and complex environment. In seawater, the selective recovery of ruthenium is favored at pH close to 10. These tests confirm the promising perspectives offered for ruthenium removal from complex environments. Physicochemical characterizations of the sorbent (and their modes of interaction with ruthenium nitrosyl) included SEM, BET, TGA, FTIR, XPS, and elemental analyses.
Ruthenium removal from complex solutions (highly saline effluents, seawater) is a critical challenge. Herein, the sorption capacity of chitosan/SiO2 composite beads (Ch-Si) for ruthenium nitrosyl is increased three-fold after phosphoramidate grafting (DPA-Ch-Si, 1.6 mmol Ru g−1) at pH 5. Uptake kinetics and sorption isotherms are compared at pH0: 3, 5 and 10; playing with the mode of agitation (mechanical, MA, vs. ultrasonic treatment, UT). The sorbent maintains good sorption capacities at pH 3 and 10. Uptake kinetics modeled by pseudo-first order rate equation is boosted by functionalization. For Ch-Si, sorption isotherms are modeled by the Langmuir or Sips equations (depending on the pH), while for DPA-Ch-Si the best fits depend on pH, temperature and mode of agitation. Ruthenium sorption is spontaneous and endothermic for the two sorbents. For DPA-Ch-Si, the sorption capacity increases from 1.62 to 1.70 mmol Ru g−1 to 2.23–2.32 mmol Ru g−1 (T increasing from 21 to 50 °C). Nitric acid solution (0.3 M) reveals highly efficient for back extraction; ruthenium is completely released in <15 min. The functionalized sorbent can be reused for a minimum of 10 cycles, with limited loss in performance. Phosphoramidation improves sorption selectivity for the treatment of equimolar multicomponent solutions (Na, Ca, Mg, Fe, Al, U, and Nd). The effect of pH on sorption selectivity is evaluated in simple multi-metal solutions and complex environment. In seawater, the selective recovery of ruthenium is favored at pH close to 10. These tests confirm the promising perspectives offered for ruthenium removal from complex environments. Physicochemical characterizations of the sorbent (and their modes of interaction with ruthenium nitrosyl) included SEM, BET, TGA, FTIR, XPS, and elemental analyses.
通讯机构：
[Liu, HB ] H;Hengyang Normal Univ, Sch Phys & Elect Engn, Hengyang 421008, Peoples R China.
摘要：
A numerical study of helicon wave heating and current driving for the HL-2M steady-state scenario has been performed. Numerical calculations based on fast wave theory show that the high frequency plays a significant role, which results in a predominance of electron absorption and negligible ion absorption. The calculations also show that the desired strong absorption region can be achieved when the frequency is greater than 420 MHz and the electron beta is higher than 1.8%. The helicon wave propagation and current drive have been simulated using GENRAY, CQL3D, and AORSA codes. Modeling analysis indicates that both the amplitude and location of the current drive simulated by these codes are in good agreement. These models also demonstrate that a remarkable off-axis current drive with a good efficiency can be obtained. Extensive scanning calculations of the wave frequency, the parallel refractive index (n & Vert;), and the poloidal location of the antenna have been conducted using GENRAY. Detailed analysis of the scanned data found that the current profile can be flexibly controlled by changing the wave frequency and the poloidal location. A smaller launched n(& Vert;) causes a part of the current to be on-axis and an increase in the total current. The helicon wave launched at or over the midplane with f = 500 MHz and n(& Vert;) = 3.8 may be a feasible scheme for HL-2M tokamaks. (c) 2025 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license(https://creativecommons.org/licenses/by/4.0/).https://doi.org/10.1063/5.0275569
摘要：
Water hyacinth is recognized as one of the top ten invasive weeds that pose significant environmental hazards globally. The resourceful utilization of water hyacinth offers substantial ecological benefits. In this work, water hyacinth is employed to synthesize a phosphorylated biochar for the efficient decontamination of uranium-containing radioactive wastewater, thereby achieving dual environmental benefits. The biochar with a large specific surface area of 1328 m2/g and a large pore volume of 0.94 cm3/g is obtained via carbonization of a freeze-dried water hyacinth-phytic acid composite. It possesses a high density of uranophilic phosphoric acid groups, with the surface phosphorus content reaching 0.78 at%. As anticipated, phosphorylated biochar demonstrates superior adsorption performance for uranium (VI) ions. The removal efficiency achieves 99 % in a uranium solution with an initial concentration of 100 mg/L at a dosage of 1.0 g/L within 30 minutes, while the maximum adsorption capacity reaches 478 mg/g. It is proficient in removing uranium across a pH range of 2.2–6.6 and exhibits tolerance under high ionic strength conditions. The distribution coefficient for uranium attains 28.5 L/g, which is significantly higher than that of many other metal ions. Moreover, the biochar is readily regenerated by elution with diluted HNO₃ and reused up to five times without any loss of efficiency. Delightfully, phosphorylated biochar effectively reduces the uranium concentration in actual nuclear wastewater from 16 μg/L to below 4 μg/L. The effective adsorptive decontamination of radioactive wastewater, followed by the incineration of spent biochar, significantly reduces the volume of radioactive waste.
Water hyacinth is recognized as one of the top ten invasive weeds that pose significant environmental hazards globally. The resourceful utilization of water hyacinth offers substantial ecological benefits. In this work, water hyacinth is employed to synthesize a phosphorylated biochar for the efficient decontamination of uranium-containing radioactive wastewater, thereby achieving dual environmental benefits. The biochar with a large specific surface area of 1328 m2/g and a large pore volume of 0.94 cm3/g is obtained via carbonization of a freeze-dried water hyacinth-phytic acid composite. It possesses a high density of uranophilic phosphoric acid groups, with the surface phosphorus content reaching 0.78 at%. As anticipated, phosphorylated biochar demonstrates superior adsorption performance for uranium (VI) ions. The removal efficiency achieves 99 % in a uranium solution with an initial concentration of 100 mg/L at a dosage of 1.0 g/L within 30 minutes, while the maximum adsorption capacity reaches 478 mg/g. It is proficient in removing uranium across a pH range of 2.2–6.6 and exhibits tolerance under high ionic strength conditions. The distribution coefficient for uranium attains 28.5 L/g, which is significantly higher than that of many other metal ions. Moreover, the biochar is readily regenerated by elution with diluted HNO₃ and reused up to five times without any loss of efficiency. Delightfully, phosphorylated biochar effectively reduces the uranium concentration in actual nuclear wastewater from 16 μg/L to below 4 μg/L. The effective adsorptive decontamination of radioactive wastewater, followed by the incineration of spent biochar, significantly reduces the volume of radioactive waste.
作者机构：
[Zhang, Le; Cai, Fei-Yang] Hubei Normal Univ, Coll Phys & Elect Sci, Huangshi 435002, Peoples R China.;[Chen, Xun; Chen, X] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
通讯机构：
[Chen, X ] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
关键词：
holographic QCD;hybrid potential;heavy quark
摘要：
Using gauge/gravity duality, we studied the exotic hybrid pseudopotentials at finite temperature and chemical potential. The Sigma hybrid meson can be described by a model including an object called "defect'' on a string linking the quark and antiquark. The Sigma(-)(u) hybrid potential at zero temperature and chemical potential was first proposed by Andreev and is perfectly described. In this study, we extended the aforementioned model to finite chemical potential and compared the separate distance and pseudopotentials of Sigma(+)(g) and Sigma u-. Unlike the Sigma(+)(g) ground state, the Sigma(-)(u) hybrid pseudopotentials no longer exhibit Coulomb-like behavior at short distances. In addition, temperature and chemical potential have a significant impact on the Sigma(-)(u) hybrid pseudopotentials. The screen distances and hybrid pseudopotentials of Sigma(-)(u) significantly decrease when increasing temperature and chemical potential. We represented the melting diagram of Sigma(+)(g) and Sigma(-)(u) in the T-mu plane and confirmed that the quark-antiquark pair in Sigma(-)(u) excited state is easier to melt than that in Sigma(+)(g) ground state.
作者：
Guo, Xi;Contreras, Miguel Angel Martin;Chen, Xun;Xiang, Dong
期刊：
中国物理C(英文),2025年49(1):013104 ISSN：1674-1137
通讯作者：
Guo, X
作者机构：
[Guo, Xi; Chen, Xun; Xiang, Dong; Contreras, Miguel Angel Martin; Guo, X] Univ South China, Sch Nucl Sci & Technol, Hengyang 421000, Peoples R China.
通讯机构：
[Guo, X ] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421000, Peoples R China.
关键词：
baryon spectroscopy;AdS/QCD;holographic QCD
摘要：
In this study, we discuss the description of neutral Sigma baryons with I(J(P))= 1(1/2(+))and I(J(P)) = 1(3/2(+)) using two bottom-up approaches: the deformed background and static dilaton models. In both models, we consider a non-linear Regge trajectory extension motivated by the strange nature of Sigma baryons. We find that both models describe these systems with an RMS error smaller than 10%. We also perform a configurational entropy calculation in both models to discuss hadronic stability.
期刊：
Chemical Engineering Journal,2025年505:159469 ISSN：1385-8947
通讯作者：
Guibal, E;Hamza, MF
作者机构：
[Salih, Khalid A. M.; Zhou, Kanggen] Cent South Univ, Sch Met & Environm, Changsha 410083, Peoples R China.;[Guibal, Eric; Guibal, E] IMT Mines Ales, Polymers Compos & Hybrids PCH, Ales, France.;[Basiony, Ebtesam A.; Nassar, Lobna A.; Abdel-Rahman, Adel A. -H.] Menoufia Univ, Fac Sci, Chem Dept, Shibin Al Kawm 32511, Egypt.;[Ning, Shunyan; Wei, Yuezhou; Hamza, Mohammed F.; Hamza, MF] Univ South China, Sch Nucl Sci & Technol, Heng Yang 421001, Peoples R China.;[Wei, Yuezhou] Shanghai Jiao Tong Univ, Sch Nucl Sci & Engn, Shanghai, Peoples R China.
通讯机构：
[Hamza, MF ] U;[Guibal, E ] I;IMT Mines Ales, Polymers Compos & Hybrids PCH, Ales, France.;Univ South China, Sch Nucl Sci & Technol, Heng Yang 421001, Peoples R China.
关键词：
Carbamoylacetamide derivative grafted-chitosan;Enhancing U(VI) sorption by ion imprinting: improved uptake kinetics and selectivity;Comparative studies of ion-imprinting and non-imprinting sorbents;Remarkable stability after 10 cycles of sorption and desorption;Efficient uranium recovery from acidic ore leachate
摘要：
Uranium recovery from complex effluents requires the combination of different processes including metal sorption from low-concentration solutions containing several competitor metal ions. The design of efficient sorbents (BTC/CH(s), 2-(benzo[d]thiazol-2-yl)-N-carbamoyl acetamide grafted chitosan) that combine both high sorption capacity and high selectivity was achieved by adopting a dual strategy: (a) selecting efficient functional groups (amine, amide, thioester, and hydroxyl groups, in BTC/CH sorbents), and (b) adapting the arrangement of reactive groups appropriately to fit the specific shape of the complexes (ion-imprinting IP vs. non-ion-imprinted NIP materials). This dual strategy was applied to design a chitosan-based sorbent with high sorption capacity (≈1.5 mmol U g −1 ), fast uptake (equilibrium: 15–20 min), remarkable stability (limited loss of performances after 10 reuse cycles), and strong selectivity (tested on both equimolar multi-component solutions and pre-treated acid leachate), at moderately acidic pH (i.e., 4). Ion-templating strategy effectively improved selectivity by 5–10-folds. Uptake kinetics was fitted by the pseudo-first order rate equation, while the sorption isotherms were finely simulated by the Temkin equation. The sorption was exothermic, spontaneous, and the ion-templating allowed reaching more organized structure. The sorbent was highly selective against base metals, alkali and alkali-earth metals, but less efficient for the separation from thorium or rare-earth elements. The sorbent was successfully used for the recovery of residual uranyl from acidic leachates pre-treated with resins (Amberlite IRA-400 and DOWEX 50, for the recovery of U and rare-earth elements, respectively) and precipitation step (removal of Al(III)/Fe(III) at pH 4). The sorbents were characterized by elemental analysis, FTIR and XPS spectroscopy for analyzing the chemical structure of the materials and identifying their interactions with U(VI). Textural properties and pHpzc values were analyzed for supporting sorption behaviors.
Uranium recovery from complex effluents requires the combination of different processes including metal sorption from low-concentration solutions containing several competitor metal ions. The design of efficient sorbents (BTC/CH(s), 2-(benzo[d]thiazol-2-yl)-N-carbamoyl acetamide grafted chitosan) that combine both high sorption capacity and high selectivity was achieved by adopting a dual strategy: (a) selecting efficient functional groups (amine, amide, thioester, and hydroxyl groups, in BTC/CH sorbents), and (b) adapting the arrangement of reactive groups appropriately to fit the specific shape of the complexes (ion-imprinting IP vs. non-ion-imprinted NIP materials). This dual strategy was applied to design a chitosan-based sorbent with high sorption capacity (≈1.5 mmol U g −1 ), fast uptake (equilibrium: 15–20 min), remarkable stability (limited loss of performances after 10 reuse cycles), and strong selectivity (tested on both equimolar multi-component solutions and pre-treated acid leachate), at moderately acidic pH (i.e., 4). Ion-templating strategy effectively improved selectivity by 5–10-folds. Uptake kinetics was fitted by the pseudo-first order rate equation, while the sorption isotherms were finely simulated by the Temkin equation. The sorption was exothermic, spontaneous, and the ion-templating allowed reaching more organized structure. The sorbent was highly selective against base metals, alkali and alkali-earth metals, but less efficient for the separation from thorium or rare-earth elements. The sorbent was successfully used for the recovery of residual uranyl from acidic leachates pre-treated with resins (Amberlite IRA-400 and DOWEX 50, for the recovery of U and rare-earth elements, respectively) and precipitation step (removal of Al(III)/Fe(III) at pH 4). The sorbents were characterized by elemental analysis, FTIR and XPS spectroscopy for analyzing the chemical structure of the materials and identifying their interactions with U(VI). Textural properties and pHpzc values were analyzed for supporting sorption behaviors.
关键词：
Uranium reduction;Cobalt oxides;Oxygen vacancies;Recovery of uranium;Radioactive wastewater
摘要：
As the primary uranium species in aquatic systems, uranyl ions (UO 2 2+ ) readily form stable coordination complexes with organic contaminants, severely compromising the recovery and utilization of uranium. To address this challenge, we developed a novel photoelectrochemical (PEC) system featuring oxygen-vacancy-enriched cobalt oxide-modified carbon felt (OvCoO x /CF) as a functional cathode. In this PEC system, the photoanode is photoexcited to generate holes (h + ) and hydroxyl radicals (•OH) efficiently decomposing organic substances, thereby releasing uranium from complexes. Concurrently, photogenerated electrons migrate through the external circuit to the OvCoO x /CF cathode, where they reduce and fix the released UO 2 2+ into stable uranium compounds while simultaneously generating electrical output. This synergistic mechanism enables the system to achieve remarkable enhancements in contaminant removal efficiency, with substantial increases in rate constants ( k ) for both uranium reduction and organic degradation. The exceptional uranium extraction performance is primarily attributed to abundant active sites, the lower adsorption energy of UO 2 2+ , and the rapid electron transfer channel introduced by the incorporation of Ov. Notably, the PEC system maintains high efficiency across diverse conditions, including pH fluctuations, high salinity and various organic contaminant species and concentrations. Furthermore, its operational robustness extends to challenging environments such as polluted seawater and natural sunlight exposure. This work establishes a sustainable paradigm for radioactive wastewater remediation, integrating efficient uranium extraction with organic pollutant elimination and in situ electricity generation, offering a transformative solution for nuclear resource recovery and environmental protection.
As the primary uranium species in aquatic systems, uranyl ions (UO 2 2+ ) readily form stable coordination complexes with organic contaminants, severely compromising the recovery and utilization of uranium. To address this challenge, we developed a novel photoelectrochemical (PEC) system featuring oxygen-vacancy-enriched cobalt oxide-modified carbon felt (OvCoO x /CF) as a functional cathode. In this PEC system, the photoanode is photoexcited to generate holes (h + ) and hydroxyl radicals (•OH) efficiently decomposing organic substances, thereby releasing uranium from complexes. Concurrently, photogenerated electrons migrate through the external circuit to the OvCoO x /CF cathode, where they reduce and fix the released UO 2 2+ into stable uranium compounds while simultaneously generating electrical output. This synergistic mechanism enables the system to achieve remarkable enhancements in contaminant removal efficiency, with substantial increases in rate constants ( k ) for both uranium reduction and organic degradation. The exceptional uranium extraction performance is primarily attributed to abundant active sites, the lower adsorption energy of UO 2 2+ , and the rapid electron transfer channel introduced by the incorporation of Ov. Notably, the PEC system maintains high efficiency across diverse conditions, including pH fluctuations, high salinity and various organic contaminant species and concentrations. Furthermore, its operational robustness extends to challenging environments such as polluted seawater and natural sunlight exposure. This work establishes a sustainable paradigm for radioactive wastewater remediation, integrating efficient uranium extraction with organic pollutant elimination and in situ electricity generation, offering a transformative solution for nuclear resource recovery and environmental protection.
摘要：
The multiple nuclides identification algorithm with low consumption and strong robustness is crucial for rapid radioactive source searching. This study investigates the design of a low-consumption multiple nuclides identification algorithm for portable gamma spectrometers. First, the gamma spectra of 12 target nuclides (including the background case) were measured to create training datasets. The characteristic energies, obtained through energy calibration and full-energy peak addresses, are utilized as input features for a neural network. A large number of single- and multiple-nuclide training datasets are generated using random combinations and small-range drifting. Subsequently, a multi-label classification neural network based on a binary cross-entropy loss function is applied to export the existence probability of certain nuclides. The designed algorithm effectively reduces the computation time and storage space required by the neural network and has been successfully implemented in a portable gamma spectrometer with a running time of
$$t_\text {r}<{2\,\textrm{s}}$$
. Results show that, in both validation and actual tests, the identification accuracy of the designed algorithm reaches 94.8%, for gamma spectra with a dose rate of
$$d\approx {0.5\,\mathrm{\upmu Sv/h}}$$
and a measurement time
$$t_\text {m}={60\,\textrm{s}}$$
. This improves the ability to perform rapid on-site nuclide identification at important sites.
摘要：
In recent years, the development of new types of nuclear reactors, such as transportable, marine, and space reactors, has presented new challenges for the optimization of reactor radiation-shielding design. Shielding structures typically need to be lightweight, miniaturized, and radiation-protected, which is a multi-parameter and multi-objective optimization problem. The conventional multi-objective (two or three objectives) optimization method for radiation-shielding design exhibits limitations for a number of optimization objectives and variable parameters, as well as a deficiency in achieving a global optimal solution, thereby failing to meet the requirements of shielding optimization for newly developed reactors. In this study, genetic and artificial bee-colony algorithms are combined with a reference-point-selection strategy and applied to the many-objective (having four or more objectives) optimal design of reactor radiation shielding. To validate the reliability of the methods, an optimization simulation is conducted on three-dimensional shielding structures and another complicated shielding-optimization problem. The numerical results demonstrate that the proposed algorithms outperform conventional shielding-design methods in terms of optimization performance, and they exhibit their reliability in practical engineering problems. The many-objective optimization algorithms developed in this study are proven to efficiently and consistently search for Pareto-front shielding schemes. Therefore, the algorithms proposed in this study offer novel insights into improving the shielding-design performance and shielding quality of new reactor types.
摘要：
We present new data on the
$$^{63}$$
Cu(
$$\gamma$$
, n) cross-section studied using a quasi-monochromatic and energy-tunable
$$\gamma$$
beam produced at the Shanghai Laser Electron Gamma Source to resolve the long-standing discrepancy between existing measurements and evaluations of this cross-section. Using an unfolding iteration method,
$$^{63}$$
Cu(
$$\gamma$$
, n) data were obtained with an uncertainty of less than 4%, and the inconsistencies between the available experimental data were discussed. The
$$\gamma$$
-ray strength function of
$$^{63}$$
Cu(
$$\gamma$$
, n) was successfully extracted as an experimental constraint. We further calculated the cross-section of the radiative neutron capture reaction
$$^{62}$$
Cu(n,
$$\gamma$$
) using the TALYS code. Our calculation method enables the extraction of (n,
$$\gamma$$
) cross-sections for unstable nuclides.
通讯机构：
[Zhang, S ; Chen, LW] A;[Chen, LW ] C;[Li, XX ] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;Adv Energy Sci & Technol Guangdong Lab, Huizhou 516000, Peoples R China.
关键词：
Classical trajectory Monte Carlo;Heavy ion-water molecule collision;Inelastic cross sections
摘要：
Inelastic collisions are the dominant cause of energy loss in radiotherapy. In the energy range around the Bragg peak, single ionization (SI) and single-electron capture (SC) are the primary inelastic collisions that lead to energy loss. This study employs the classical trajectory Monte Carlo method to study the SI and SC processes of H
$$_{2}$$
O molecules using He
$$^{2+}$$
and C
$$^{6+}$$
projectiles in the energy range of 10 keV/u to 10 MeV/u. The total cross sections, single differential cross sections, impact parameter dependence of SI and SC, and fragmentation cross sections were investigated. Results illustrate that the cross section for SI is the highest when the projectile energy is close to the Bragg peak energy. When the projectile energy is below the Bragg peak energy, the ionized electrons in the forward direction dominate, and the removal of electrons can be associated with large impact parameters. As the projectile energy increases, the emission angle of the electrons gradually transitions from small angles (
$$0^{\circ} \sim 30^{\circ}$$
) to large angles (
$$60^{\circ} \sim 120^{\circ}$$
), and the removal of electrons is associated with small impact parameters. The energy distributions of the ionized electron are similar when the projectile energy is equal to, below or above the Bragg peak energy. The fragmentation cross sections after SI and SC in the energy range around the Bragg peak were also estimated.
摘要：
Mn 0.4 Zn 0.6 Fe 2-2 x Cr 2 x O 4 ( x = 0, 0.1, 0.2, 0.3, and 0.4) powder samples were prepared using the sol-gel method. X-ray powder diffraction (XRD) showed that all samples belong to the cubic spinel crystal system with an Fd-3m space group. The Scanning Electron Microscope (SEM) results show that the substitution of Cr leads to a reduction in grain size. The magnetothermal curves obtained from the Multi-Purpose Physical Property Measurement System (PPMS-9) indicated the presence of a spin glass state at low temperatures. With increasing Cr 3+ doping, the Curie temperature decreased and dropped below room temperature at x = 0.4. The unsaturated hysteresis loops of the samples reveal the presence of anomalous paramagnetism below the Curie temperature. Mössbauer spectrum confirmed the coexistence of ferromagnetism and paramagnetism at room temperature. Mössbauer spectrum analysis indicates an interesting superparamagnetic cluster phenomenon caused by the presence of excess non-magnetic ions in the sample. Additionally, Cr doping altered the distribution of metal ions in the samples, causing fluctuations in the area of the superparamagnetic clusters, which verifies that this phenomenon is primarily driven by the magnetic behavior influenced by non-magnetic ions.
Mn 0.4 Zn 0.6 Fe 2-2 x Cr 2 x O 4 ( x = 0, 0.1, 0.2, 0.3, and 0.4) powder samples were prepared using the sol-gel method. X-ray powder diffraction (XRD) showed that all samples belong to the cubic spinel crystal system with an Fd-3m space group. The Scanning Electron Microscope (SEM) results show that the substitution of Cr leads to a reduction in grain size. The magnetothermal curves obtained from the Multi-Purpose Physical Property Measurement System (PPMS-9) indicated the presence of a spin glass state at low temperatures. With increasing Cr 3+ doping, the Curie temperature decreased and dropped below room temperature at x = 0.4. The unsaturated hysteresis loops of the samples reveal the presence of anomalous paramagnetism below the Curie temperature. Mössbauer spectrum confirmed the coexistence of ferromagnetism and paramagnetism at room temperature. Mössbauer spectrum analysis indicates an interesting superparamagnetic cluster phenomenon caused by the presence of excess non-magnetic ions in the sample. Additionally, Cr doping altered the distribution of metal ions in the samples, causing fluctuations in the area of the superparamagnetic clusters, which verifies that this phenomenon is primarily driven by the magnetic behavior influenced by non-magnetic ions.
通讯机构：
[Wang, F ] B;Beijing Inst Technol, Sch Phys, Beijing 100081, Peoples R China.
摘要：
We conducted a study on the electron stopping power of protons in aluminum at finite electron temperatures, utilizing time-dependent density functional theory nonadiabatically coupled with molecular dynamics. Our investigation focused on protons with initial velocities ranging from 0.1 to 1.0 a.u., providing a wealth of detailed information on the electronic states involved in the stopping process, with exceptional spatial and temporal resolution. Our results show that the electron temperature can significantly effect the electron stopping power. A quantum-blocking mechanism based on a physical picture of electronic transitions in energy levels has been proposed for explaining the phenomenon of electron stopping power decreasing with the increase of target electron temperature.
摘要：
The design of complex reactor shielding structures requires consideration of neutron and photon radiation levels in various regions, as well as trade-offs in weight, volume, and cost, leading to a substantial increase in shielding calculation parameters and optimization objectives. This study introduces a high-dimensional multi-objective shielding optimization method based on a multi-parameter shielding calculation surrogate model, with significant improvements to the FCNN-NSGAIII shielding optimization method which integrates a neural network with a genetic algorithm. For the optimization of complex reactor shielding structures under diverse source item energy spectra, the multi-parameter surrogate model achieves a prediction error reduction of an order of magnitude to 3.65% compared to traditional neural networks. Furthermore, the k_NSGAIII optimization algorithm, enhanced with a knee-point strategy, demonstrates a greater relative set coverage indicator than the NSGAIII algorithm, indicating its ability to identify superior shielding design schemes.
The design of complex reactor shielding structures requires consideration of neutron and photon radiation levels in various regions, as well as trade-offs in weight, volume, and cost, leading to a substantial increase in shielding calculation parameters and optimization objectives. This study introduces a high-dimensional multi-objective shielding optimization method based on a multi-parameter shielding calculation surrogate model, with significant improvements to the FCNN-NSGAIII shielding optimization method which integrates a neural network with a genetic algorithm. For the optimization of complex reactor shielding structures under diverse source item energy spectra, the multi-parameter surrogate model achieves a prediction error reduction of an order of magnitude to 3.65% compared to traditional neural networks. Furthermore, the k_NSGAIII optimization algorithm, enhanced with a knee-point strategy, demonstrates a greater relative set coverage indicator than the NSGAIII algorithm, indicating its ability to identify superior shielding design schemes.
摘要：
This study systematically investigates the evolution of vacancy-type defects and heterogeneous Cu nanoprecipitates in an Fe60Cr12Mn8Cu15Mo3V2 (at%) multi-principal element alloy during thermal processing, utilizing Positron annihilation lifetime spectroscopy (PAS), coincidence Doppler broadening (CDB) spectroscopy, and transmission electron microscopy (TEM). The results show that the alloy exhibited a dual-phase coexistence structure of Body-Centered Cubic (BCC) and Face-Centered Cubic (FCC). The CDB results show that the density of heterogeneous Cu precipitates gradually increases with annealing temperature. Compared to the as-cast alloy, the precipitates annealed at 773 K exhibit a significantly reduced size (approximately 33 nm) with higher density. The PAS results demonstrate that gradual migration and aggregation of monovacancies at 573 K form vacancy clusters, while contraction and dissociation of these clusters dominate at 673 K. Within the temperature range of 773-973 K, the dynamic equilibrium between the aggregation and decomposition of vacancy clusters maintains stable annihilation characteristics with minimal lifetime changes.
作者机构：
[Chen, YD; Chen, Yidian] Hangzhou Normal Univ, Sch Phys, Hangzhou 311121, Peoples R China.;[Chen, Xun] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Chen, Xun] Cent China Normal Univ, Key Lab Quark & Lepton Phys MOE, Wuhan 430079, Peoples R China.;[Li, Danning] Jinan Univ, Dept Phys, Guangzhou 510632, Peoples R China.;[Li, Danning] Jinan Univ, Siyuan Lab, Guangzhou 510632, Peoples R China.
通讯机构：
[Chen, YD ] H;Hangzhou Normal Univ, Sch Phys, Hangzhou 311121, Peoples R China.
摘要：
We investigate the effects of rotation on deconfinement and chiral phase transitions in the framework of the dynamical holographic QCD model. Instead of transforming to the rotating system by Lorentz boost, we construct an anisotropic gravitational background by incorporating the rotating boundary current. We first investigate the pure gluon system under rotation to extract deconfinement phase transition from the Polyakov loop then add two-flavor probe for chiral restoration phase transition from the chiral condensate. It is observed that at low chemical potentials, the deconfinement phase transition of pure gluon system is of first order and the chiral phase transition of a two-flavor system is of crossover. Both the critical temperatures of deconfinement and chiral phase transitions decrease/increase with imaginary/real angular velocity (Omega(I)/Omega) as T/T-c similar to 1 - C-2 Omega(2)(I) and T/T-c similar to 1 + C-2 Omega(2), which is consistent with lattice QCD results. In the temperature-chemical potential T - mu phase diagram, the critical end point moves toward regions of higher temperature and chemical potential with real angular velocity.
通讯机构：
[Luo, W ; Krasny, MW ] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;Minist Educ, Key Lab Adv Nucl Energy Design & Safety, Hengyang 421001, Peoples R China.;Univ Paris Sorbonne, LPNHE, F-75005 Paris, France.;CERN, CH-1211 Geneva, Switzerland.
关键词：
Nuclear transmutation;Long-lived fission products;Gamma Factory;Advanced nuclear energy system
摘要：
The Gamma Factory (GF) project aims to generate high-intensity \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\gamma$$\end{document}-ray beams of tunable energy and relatively small energy spread. Such beams can be optimized to generate an intense photo-neutron source, capable of driving an advanced nuclear energy system (ANES) for nuclear waste transmutation and supplying electrical power that is necessary for the GF operation mode of the Large Hadron Collider storage ring. In this study, we investigate the feasibility of driving ANES with the GF beam which is optimized to maximize the neutron production rate. The dependence of the ANES thermal power on the distance between the positions of the ANES and the GF \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\gamma$$\end{document}-ray source is evaluated. For the \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\gamma$$\end{document}-ray beam reaching the intensity of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\sim 10<^>{19}$$\end{document} photons per second, the ANES thermal power could exceed 500 MWt. Under the assumption that ANES operates over 20 years, the transmutation rate could reach \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$30\%$$\end{document} for five typical long-lived fission products (LLFPs): \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$<^>{79}$$\end{document}Se, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$<^>{99}$$\end{document}Tc, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$<^>{107}$$\end{document}Pd, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$<^>{129}$$\end{document}I, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$<^>{137}$$\end{document}Cs. Our comparative studies show that although the neutron production efficiency of the GF \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\gamma$$\end{document}-ray beam (per MW of the beam power) is approximately 14 times lower than that of the 500 MeV proton beam, the overall net ANES power production efficiency for the GF beam driver scheme could be comparable to that of the proton beam driver scheme, while providing additional transmutation capacity, not available for the proton beam driven scheme. It is suggested that the GF-driven ANES could provide a viable solution for the efficient transmutation of the loaded LLFPs with no prior isotopic separation, and generate the requisite electrical power for its operation, with reduced production of LLFPs over its operation cycle.
摘要：
This study investigates factors influencing the leaching process in uranium mining, using a uranium mine in Inner Mongolia, China, as a representative case. We used PHREEQC geochemical and COMSOL Multiphysics® software, as well as the coupling interface COMSOL PHREEQC (iCP), to simulate acid leaching of underground core mineral samples. The study systematically analyzes the effects of sulfuric acid concentration, permeability coefficient, and injection/leaching pressure differential on uranium leaching efficiency. It also reveals spatial and temporal variations of minerals throughout the leaching process. The findings include a positive correlation between sulfuric acid concentration and leaching rate. Increased permeability significantly enhanced the leaching effect, while the injection/leaching pressure differential had an optimal range. Additionally, mineral evolution characteristics suggested that acidophilic minerals dissolve rapidly in initial stages, whereas later stages may involve minerals such as kaolinite and quartz influencing pore structure. These findings provide a foundation for optimizing process parameters in uranium mining and offer a quantitative reference for micro-scale mineral changes, ultimately for efficient and sustainable uranium extraction.
摘要：
Intelligent fault diagnosis (IFD) plays a crucial role in reducing maintenance costs and enhancing the reliability of safety-critical energy systems (SCESs). In recent years, deep learning-based IFD methods have achieved high fault diagnosis accuracy extracting implicit higher-order correlations between features. However, the excessive long training time of deep learning models conflicts with the requirements of real-time analysis for IFD, hindering their further application in practical industrial environments. To address the aforementioned challenge, this paper proposes an innovative IFD method for SCES that combines the particle swarm optimization (PSO) algorithm and the ensemble broad learning system (EBLS). Specifically, the broad learning system (BLS), known for its low time complexity and high classification accuracy, is adopted as an alternative to deep learning for fault diagnosis in SCES. Furthermore, EBLS is designed to enhance model stability and classification accuracy with high-dimensional small samples by incorporating the random forest (RF) algorithm and an ensemble strategy into the traditional BLS framework. In order to reduce the computational cost of the EBLS, which is constrained by the selection of its hyperparameters, the PSO algorithm is employed to optimize the hyperparameters of the EBLS. Finally, the model is validated through simulated data from a complex nuclear power plant (NPP). Numerical experiments reveal that the proposed method significantly improved the diagnostic efficiency while maintaining high accuracy. In summary, the proposed approach shows great promise for boosting the capabilities of the IFD models for SCES.
期刊：
OPTICS AND LASER TECHNOLOGY,2025年180:111544 ISSN：0030-3992
通讯作者：
Li, Y
作者机构：
[Luo, Xiao-Qing; Lu, Zhendong; Chen, Sha; Zhou, Yaojie; Liu, Qinke] Univ South China, Sch Elect Engn, Hengyang 421001, Peoples R China.;[Li, Yan] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Liu, W. M.] Chinese Acad Sci, Beijing Natl Lab Condensed Matter Phys, Inst Phys, Beijing 100190, Peoples R China.
通讯机构：
[Li, Y ] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
关键词：
All-dielectric metasurface;Bound states in the continuum;Refractive index sensing
摘要：
The quasi-bound states in the continuum (QBIC) have drawn increasing attention in optical metasurfaces derived from their ultrahigh quality factors, and show the utility to enhance the sensitivity of optical sensing. However, conventional single-resonance sensing may be inaccurate and unreliable, and then the dual-resonance sensing governed by the coupled QBIC is desired but remains elusive. Here, we show that the coupled QBIC modes can be leveraged to unfold dual-resonance refractive index sensing in the hybrid all-dielectric metasurface. Specifically, it is revealed that the toroidal dipole mode can be realized with strong electric field enhancement, enabling the implementation of anapole mode in the telecom short-wavelength band (1460–1530 nm). Under different linearly polarized illuminations, the dual symmetry-protected QBIC modes dominated by the electric quadrupole resonance can be fulfilled in the telecom extended-wavelength band (1360–1460 nm). Within this framework, the polarization-dependent dual symmetry-protected QBIC modes selectively coupled with the toroidal dipole mode or the anapole mode can not only uncover the transformation from Fano resonance to analog of electromagnetically induced transparency, but also manifest two types of high-sensitivity dual-resonance refractive index sensing in the telecom extended-wavelength and short-wavelength bands. The dual-resonance refractive index sensing can also be extended to telecom long-wavelength band (1565–1625 nm) and ultra-long-wavelength band (1625–1675 nm) with enhanced sensitivity. These results offer exploration potential for multi-channel sensing, optical modulators, and slow-light devices.
The quasi-bound states in the continuum (QBIC) have drawn increasing attention in optical metasurfaces derived from their ultrahigh quality factors, and show the utility to enhance the sensitivity of optical sensing. However, conventional single-resonance sensing may be inaccurate and unreliable, and then the dual-resonance sensing governed by the coupled QBIC is desired but remains elusive. Here, we show that the coupled QBIC modes can be leveraged to unfold dual-resonance refractive index sensing in the hybrid all-dielectric metasurface. Specifically, it is revealed that the toroidal dipole mode can be realized with strong electric field enhancement, enabling the implementation of anapole mode in the telecom short-wavelength band (1460–1530 nm). Under different linearly polarized illuminations, the dual symmetry-protected QBIC modes dominated by the electric quadrupole resonance can be fulfilled in the telecom extended-wavelength band (1360–1460 nm). Within this framework, the polarization-dependent dual symmetry-protected QBIC modes selectively coupled with the toroidal dipole mode or the anapole mode can not only uncover the transformation from Fano resonance to analog of electromagnetically induced transparency, but also manifest two types of high-sensitivity dual-resonance refractive index sensing in the telecom extended-wavelength and short-wavelength bands. The dual-resonance refractive index sensing can also be extended to telecom long-wavelength band (1565–1625 nm) and ultra-long-wavelength band (1625–1675 nm) with enhanced sensitivity. These results offer exploration potential for multi-channel sensing, optical modulators, and slow-light devices.
