47Sc, as a promising theranostic radionuclide, makes the separation of Sc3+ from Ca2+ highly significant for the production of 47Sc from 46Ca targets. Herein, a novel 40 wt% DMHMP/CG71M resin was prepared by impregnating macroporous CG71M with di(1-methyl-heptyl) methyl phosphonate (DMHMP). Subsequently, its adsorption behavior for Sc3+ and Ca2+ was examined using batch experiments and column tests. This resin showed excellent selective adsorption capacity for Sc3+ in HCl solution. Moreover, the pseudo-second-order kinetic and Langmuir isotherm models were used to analyze the adsorption process of Sc3+, revealing a monolayer chemisorption mechanism with a maximum capacity of 25.6 mg/g. Furthermore, the resin was applied to the separation of 47Sc from irradiated 46Ca targets, successfully yielding approximately 582.75 GBq of 47Sc with radionuclide purity over 99.5 %. Overall, with its mild synthesis conditions, efficient selective adsorption, and simple operation, the DMHMP/CG71M resin is a promising separation material for the production of 47Sc.

Short-range correlation (SRC) in nuclei refers to nucleons forming temporally correlated pairs in close proximity, giving rise to the high momentum of the nucleons beyond the Fermi surface. It has been reported that bremsstrahlung gamma production from the neutron-proton process in heavy-ion reactions provides a potential probe to the SRC abundance in nuclei. In this paper, we present in detail the precision measurement of bremsstrahlung gamma rays in 124Sn + 124Sn reactions at 25 MeV/nucleon using the Compact Spectrometer for Heavy IoN Experiment (CSHINE). A comprehensive experimental and analysis framework is established to ensure the reliability and robustness of the extracted results. Background contributions are evaluated and subtracted using independent methods, and the consistency of the analysis is systematically validated. By comparing the experimental gamma spectrum with isospin-dependent Boltzmann-Uehling-Uhlenbeck simulations, the high momentum tail (HMT) fraction of RHMT = (20 +/- 3)% is derived in 124Sn nuclei. This work provides a detailed and validated experimental framework for extracting SRC information from bremsstrahlung gamma-ray emission and demonstrates the feasibility of studying nucleon SRCs with high precision in low-energy heavy-ion collisions.

Abstract This study reports on the design, simulation, construction, and testing of a full-size prototype of the multi-wire drift chamber for the CSR external-target experiment. The multi-wire drift chamber array incorporates drift cells of three different sizes: 8 $$\times $$ × 8 mm $$^{\textrm{2}}$$ 2 , 10 $$\times $$ × 10 mm $$^{\textrm{2}}$$ 2 , and 15 $$\times $$ × 15 mm $$^{\textrm{2}}$$ 2 . Simulation studies were carried out to compare their electron drift time spectra, R-T relations, and position resolution. The prototype was constructed based on the design of the multi-wire drift chamber closest to the target. Since the beam passes through the center region of the multi-wire drift chamber, the prototype features a special beam avoidance design. The design ensures that the detector is sensitive to reaction products while remaining unresponsive to heavy ion beams. The size of the prototype is 930 $$\times $$ × 1660 mm $$^{\textrm{2}}$$ 2 , comprising 960 drift cells. Testing was conducted with dedicated electronics. An energy resolution of 22% was achieved for the $$^{\textrm{55}}$$ 55 Fe source; the track residuals were approximately 300 $$\upmu $$ μ m for the cosmic rays; the detection efficiency of each layer exceeds 96% for the cosmic rays.

The past decade(2016-2025)marks a strategic transition period for China's isotope technology to transform from reliance on imports to independent innovation.To systematically analyze the breakthroughs and existing challenges in this field,this paper examines seven key areas over the past decade:national policy planning,production facility construction,research and development of core technologies,market entry of isotope products,radioactive source applications,radiopharmaceuticals,industrial park layout,and R&D platform construction.It integrates policy documents,technical reports,and industrial data,conducts a comprehensive review and summary,and analyzes existing issues and shortcomings.Suggestions for subsequent development have been proposed in response to the identified issue.

Heavy-ion collisions(HICs)is a unique experimental tool for investigating the properties of nuclear matter under extreme conditions in the laboratory.At HIRFL-CSR energies,HICs can create nuclear matter with 2-3 times the saturation density(ρ0).The HIRFL-CSR external-target experiment(CEE)is a large-acceptance spectrometer designed to explore frontier top-ics in high-energy nuclear physics,such as the QCD phase structure and nuclear matter equation of states.In this letter,we introduce simulation and analysis software for the CEE experiment(CeeROOT).Based on the CEE conceptual design and CeeROOT software,the configurations of its subdetectors were optimized by considering foreseeable physical constraints.The final detector layout of the CEE spectrometer and its acceptances were validated through simulations of U+U collisions at 500 MeV/u and pp collisions at 2.8 GeV,which demonstrated that the CEE experiment will serve as a detector with wide acceptance and multi-particle identification capabilities for studying high-energy nuclear physics topics at HIRFL-CSR energies with pp,pA,and AA collisions.

Nuclear energy, as a safe, low-carbon, stable, and efficient clean energy source, demonstrates broad development prospects in global energy transition and climate change mitigation. Uranium is a key raw material for nuclear energy, and its demand continues to grow with the rapid development of the nuclear industry. Seawater contains abundant uranium reserves, nearly a thousand times that of terrestrial uranium. Therefore, uranium extraction from seawater is crucial for the sustainable development of nuclear energy. Currently, there are various methods for seawater uranium extraction, such as adsorption, ion exchange, membrane separation, photocatalysis, and electrochemical methods. However, each method has its own advantages and disadvantages. Combining different methods to leverage their strengths can potentially improve uranium extraction efficiency. In this study, a porous composite aerogel material, PAO/g-C3N4, was prepared by first combining adsorbent and photocatalytic materials into a hydrogel through molecular crosslinking, followed by freeze-drying. The material was characterized by SEM, FTIR, XRD, and other techniques. Batch experiments were conducted to investigate the effects of solid-to-liquid ratio, pH, ionic strength, contact time, and initial concentration on adsorption performance. The results show that the prepared aerogel material has a porous network structure, which exposes more active sites and increases the contact opportunities between the material and uranyl ions. Additionally, the composite aerogel PAO/g-C3N4 retains the original properties of its components. Adsorption experiments indicate that both PAO/g-C3N4 and PAO follow pseudo-second-order kinetics, with optimal uranium adsorption under near-neutral conditions. The uranium adsorption capacity of PAO fits the Langmuir adsorption model, suggesting monolayer chemical adsorption. In contrast, the uranium extraction capacity of PAO/g-C3N4 does not reach saturation within the studied concentration range, indicating its excellent uranium extraction capability. The uranium extraction performance of both PAO/g-C3N4 and PAO is influenced by pH and ionic strength, suggesting that inner-sphere and outer-sphere complexation may be the adsorption mechanism. Moreover, PAO/g-C3N4 exhibits good reusability and ion selectivity. In simulated seawater with extremely low uranium concentration, PAO/g-C3N4 shows higher uranium extraction than PAO. Mechanistic analysis reveals that PAO relies solely on adsorption, while PAO/g-C3N4 combines both adsorption and photocatalysis. The amidoxime groups in PAO primarily coordinate with uranyl ions, while g-C3N4 acts as a photocatalyst. Due to the presence of dissolved oxygen during the experiment, the photocatalytic product of g-C3N4 is uranyl peroxide dihydrate. Under the combined effects of adsorption and photocatalysis, PAO/g-C3N4 achieves efficient uranium extraction, demonstrating potential for practical applications. Furthermore, this study provides a new approach for the synergistic application of adsorption and photocatalysis.

The Richardson-Lucy algorithm is applied to reconstruct the three-dimensional source function of identical pions from their two-particle correlation functions. The algorithm's performance is first evaluated through simulations with Gaussian-type initial source functions. Its imaging quality and robustness are further demonstrated with experimental data from Au+Au collisions at 1.23 A GeV, collected by the HADES Collaboration. Additionally, using UrQMD simulations of Pb+Pb collisions at 1.5 A GeV, we show that the deblurred source functions exhibit sensitivity to the initial neutron skin thickness of the colliding nuclei. This highlights the potential of the Richardson-Lucy algorithm as a tool for probing the neutron density distribution in heavy nuclei.

We have developed a systematic approach to calculate the correlation function for spin-1/2 particles, incorporating both central and noncentral components of the interparticle interaction. This is achieved by extending the variable phase method to accommodate noncentral potentials and numerically solving the Schrödinger equation. Within this framework, the partial-wave contributions to the nucleon-nucleon correlation functions adopting the Reid soft-core potential are evaluated. The resulting correlation functions are then compared for Gaussian sources of different sizes.

This work developed an efficient method for fabricating hundred becquerel-level 227Ac radioactive sources. By integrating a refined purification process with an optimized molecular plating technique, a deposition efficiency exceeding 98% was achieved. The prepared source was successfully employed to calibrate the energy and time resolution of the thermochromatography-LEGEND system. The principal novelty of our approach lies in addressing the challenge of impurity control during the deposition of trace amounts of actinide elements, thereby providing a reliable radioactive source for online/offline calibration of the alpha detectors.

Deep eutectic solvents (DESs) are biodegradable, low-toxicity mixtures that can effectively dissolve rare earth oxides, offering a sustainable alternative to corrosive acids in the recycling of rare earth elements. In this study, three betaine-based DESs were prepared by combining betaine with lactic acid, glycolic acid, or levulinic acid at a molar ratio of 1:4. These solvents exhibited high solubility for light and medium rare earth oxides. The influence of water content on the physicochemical properties of the betaine-based DESs and their capacity to dissolve rare earth oxides was systematically investigated. Furthermore, molecular dynamics simulations were performed to examine the behavior of the betaine-based DESs in the presence of water. All betaine-based DESs displayed higher affinity and selectivity for light rare earth elements compared to medium and heavy rare earths. The addition of water reduced the viscosity and modified other physicochemical properties of the betaine-based DESs. Simulations indicated that water alters the hydrogen-bonding network of DESs, which correlates with changes in their physicochemical properties and rare earth oxide solubility. The dissolution behavior of rare earth oxides in the betaine-based DESs was further characterized by UV-Vis absorption, infrared spectroscopy, Xray diffraction, and mass spectrometry. Results demonstrated that water plays a critical role in modulating the dissolution of rare earth oxides. Moreover, the betaine-based DESs with different water contents showed distinct solubility patterns for light, medium, and heavy rare earth oxides. Mechanistic analysis revealed that the dissolution efficiency of betaine-based DESs is influenced by the nature and speciation of the rare earth oxides. The findings of this study provide valuable insights for the separation of rare earth oxides using betaine-based DESs.

47Sc, as a promising theranostic radionuclide, makes the separation of Sc3+ from Ca2+ highly significant for the production of 47Sc from 46Ca targets. Herein, a novel 40 wt% DMHMP/CG71M resin was prepared by impregnating macroporous CG71M with di(1-methyl-heptyl) methyl phosphonate (DMHMP). Subsequently, its adsorption behavior for Sc3+ and Ca2+ was examined using batch experiments and column tests. This resin showed excellent selective adsorption capacity for Sc3+ in HCl solution. Moreover, the pseudo-second-order kinetic and Langmuir isotherm models were used to analyze the adsorption process of Sc3+, revealing a monolayer chemisorption mechanism with a maximum capacity of 25.6 mg/g. Furthermore, the resin was applied to the separation of 47Sc from irradiated 46Ca targets, successfully yielding approximately 582.75 GBq of 47Sc with radionuclide purity over 99.5 %. Overall, with its mild synthesis conditions, efficient selective adsorption, and simple operation, the DMHMP/CG71M resin is a promising separation material for the production of 47Sc.

Actinium-225 (225Ac) is a pivotal alpha-emitting radionuclide for targeted alpha therapy (TAT), while the large-scale production and purification strategy from thorium fissions often result in 225Ac solutions with high acidity and are hard for radiopharmaceutical labeling. Considering the conventional acid removal methods from 225Ac solutions face challenges, a radiation-tolerant graphene oxide-carbon quantum dots (GO-CQDs) composite membrane was prepared for 225Ac3+ solution deacidification. Owing to radioactivity constraints, La3+ was used as a non-radioactive surrogate for Ac3+ since their chemical similarity and comparable hydrated ionic diameters. Membrane structure was optimized by tuning interlayer spacing (d-spacing) and thickness, the membrane with minimum d-spacing and thickness of 65 nm was achieved to ensure the efficient permeation of H+ and rejection of La3+. The GO-CQDs membrane demonstrated superior acid removal performance in HNO3, HCl, and H2SO4 media, especially in HNO3 solution, the highest H+/La3+ separation factor of 55.01 was obtained. Crucially, the membrane not only retained functionality after 100 kGy gamma-irradiation, but also compensated for the intrinsic defects of commercial deacidification membrane in nitric acid medium. This work establishes GO-CQDs membrane as a robust, radiation-tolerant material for trivalent radioisotope solution deacidification.

The neutron-neutron (nn) correlation function has been measured in 25  MeV/u ^{124}Sn+^{124}Sn reactions. Using the Lednický-Lyuboshitz approach, the nn scattering length and effective range (f_{0}^{nn}, d_{0}^{nn}), as well as the reduced space-time size R^{(0)} of the neutron emission source are simultaneously extracted as (18.9_{-1.2}^{+1.3}  fm, 1.9_{-1.0}^{+1.3}  fm) and 4.12±0.12  fm, respectively. The measured nn scattering length is consistent with the results obtained in the low-energy scattering ^{2}H(π^{-},γ)2n, indicating heavy-ion collisions can serve as an effective approach for measuring nn interactions and further investigating the charge symmetry breaking of nuclear force. The space-time size extracted from momentum-gated correlation functions exhibits clear dependence on the pair momentum, with R^{(0)}=2.8±0.1  fm and 4.9±0.2  fm being determined for the high and low momentum neutrons, respectively.

Towards the goal of accelerator-based 225Ac production from proton and nitrogen irradiated natural thorium targets, this work hereby presents a self-designed preparation system that allows for continuous operation with improved multi-column ion-exchange method. The system with advantageous features validated the feasibility of the automatic separation and purification of actinium from hundreds of impurity nuclides. Through automated experiments with multiple targets, the recovery yield and the radionuclide purity of final 225Ac products was stabilized to be around 63 % and 92 % - 96 %, respectively. The total content of stable impurities is measured to be less than 2.4 mu g in the final actinium product. The radioactivity levels of 226Ac and 227Ac in the product are evaluated over time. Based on the results of evaluation, the optimal time to start separation is determined to be around the 10th day after the end of bombardment. Additionally, the 225Ac-PSMA-617 compound was synthesized with the 225Ac product that meets the requirement of nuclear medicine.

Thermochromatography is widely used in studying the chemical properties of superheavy elements (SHEs) due to its fast and high efficiency, which requires the detector to accurately measure both the position and energy of charged particles emitted by radioactive elements across a range of temperature distributions. 4H-SiC detectors are conducive to work at high temperature environments due to its unique properties. A 4H-SiC Schottky diode array detector for the detection of Nh (Z = 113) elements by thermochromatography is designed and fabricated in this work. An 80 mu m thick 4H-SiC epitaxial layer with a doping concentration of lowing than 1 x 1014 cm- 3 was designed to achieve a total energy deposition of alpha particles. The leakage current is 82 nA under -200 V at 80 degrees C. By linear fitting, the relationship between the deposition energy and channel number is expressed as y = 4.72x-166.71, with an R-squared value of 0.9984. The detector's energy resolution in air at 80 degrees C is 1.83% @5486 keV, which is consistent with the 1.75%@5486 keV measured at 26 degrees C in air. The energy resolutions of the array detector for 241Am under vacuum ranges from 1.18% to 1.34%, corresponding to a mean spectrum broadening of 69.26 +/- 7.51 keV. 4H-SiC detectors satisfy the thermochromatography requirements for operating temperature, energy resolution, energy linearity, and device uniformity, which will be used for Nh elements study in the following experiments.

By combining femtoscopic interferometry with an optical deblurring algorithm, we present a novel method to image the source in heavy-ion collisions (HICs), while simultaneously determining the interaction strength between particle pairs. The spatial distribution of the emission source has been reconstructed for protons (p) and antiprotons ( p ) from the respective pp and pp correlation functions in Au+Au collisions at SNN=200 GeV. Within experimental uncertainties, protons and antiprotons share the same freeze-out distribution showing higher density in the center compared to the widely assumed Gaussian shape. The results evidence the matter-antimatter symmetry in coordinate space at the freeze-out moment before the nucleons are fully randomized in the collisions.

To evaluate the suitability of 47Sc for SPECT imaging and therapeutic effect, a fibroblast activation protein (FAP) inhibitor FAPI-46 was used for cancer theranostics in preclinical setting. 47Sc was successfully produced via thermal neutron irradiation of 46Ca and then conjugated with FAPI-46, achieving a high radiochemical purity over 98

Superheavy elements(SHEs), defined as elements with atomic numbers greater than 103, represent a frontier in nuclear and chemical sciences. These elements, which include rutherfordium(Rf) through oganesson(Og), are not exist in nature and currently can only be artificially synthesized using heavy-ion accelerators. The production of SHEs is characterized by extremely low yields, often resulting in only “one-atom-at-a-time” level, and all their isotopes have short half-lives, typically ranging from milliseconds to seconds. These characteristics preclude their detection through conventional chemical analysis techniques, resulting in limited understanding of their chemical properties and behavior. In addition, with the increasing atomic number, relativistic effects become increasingly pronounced, significantly impacting the physical and chemical properties of SHEs. Consequently, the chemical behavior of SHEs deviates markedly from periodicity-based predictions for their lighter homologs. To be precise, the position of a new element in the periodic table can only be definitively assigned after verifying its chemical property. Therefore, investigating the chemical properties of SHEs is a critical research issues in nuclear chemistry. In this case, gas phase chromatography technique was developed as a distinctive and effective method for examining the volatility, adsorption enthalpy, and other essential physicochemical parameters of short-lived SHEs. Through such approaches, researchers can infer the chemical behavior of single atoms of superheavy elements and compare them with predictions from relativistic quantum chemical calculations. This review systematically explores advancements in the gas-phase chemistry of SHEs, encompassing historical developments, experimental methodologies, recent discoveries, status and progress in China. Its objective is to clarify the impact of relativistic effects on their electron configurations and their precise positions within the periodic table. The article reviews the discovery process of SHEs, from the pioneering efforts in the late 20th century until more recent achievements in synthesizing of the heaviest element, and highlights significant technological advancements in their chemical research, including the developments of target preparation and gas chromatography technology. Moreover, the detailed insights into recent experimental methods and results concerning carbonyl complexes of seaborgium(Sg), bohrium(Bh), hassium(Hs), meitnerium(Mt) and their homologues, as well as the chemical properties of copernicium(Cn), nihonium(Nh), flerovium(Fl), and even moscovium(Mc) in their elemental states are presented. Recent studies confirm that, although the chemical properties of SHEs generally follows the periodic trends observed in their lighter homologs, they also exhibit deviations due to the strong relativistic effects on the electron configurations. From a future perspective, anticipated advancements in experimental techniques and theoretical models will further elucidate the underlying principles of the periodic table and enable the exploration of heavier elements.

A half-size prototype of the multi wire drift chamber for the cooling storage ring external-target experiment (CEE) was assembled and tested in the 350 MeV/u Kr + Fe reactions at the heavy-ion research facility in Lanzhou. The prototype consists of six sense layers, where the sense wires are stretched in three directions X, U, and V; meeting 0^∘ , 30^∘ , and -30^∘ , respectively, with respect to the vertical axis. The sensitive area of the prototype is 76 cm× 76 cm . The amplified and shaped signals from the anode wires were digitized in a serial capacity array. When operating at a high voltage of 1500 V on the anode wires, the efficiency for each layer is greater than 95 301 ± 2 μm . This performance satisfies the requirements of CEE.