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BackgroundThe separation and removal of fission products and the recovery of carrier molten salt during nuclear fuel reprocessing in molten salt reactors reduces waste and facilitates useful substance recycling.PurposeThis study aims to separate and remove the rare earth (RE) fission products and recovery of carrier molten salts.MethodsFirstly, high temperature precipitation reactions of rare earth (RE = Ce, Nd, Sm, Eu, Y, Yb) and thorium fluorides were studied in LiF-BeF2 melt using sodium sulfide hydate (Na2S·5H2O) as the precipitant. Their removal ratios were subsequently compared under different conditions. Then, a combined precipitation distillation method was employed to further heat the precipitated mixed salt to 950 °C and distilled under vacuum conditions at a pressure of 10 Pa for 20 min. The content and removal ratio of rare earth Nd, as well as contents of oxygen and sulfur, in condensed collected salts were investigated after using above improved precipitation-distillation processing. Finally, further analysis of the composition of sediment was conducted using X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS) and Energy Dispersive Spectrometer (EDS).ResultsThe results demonstrate that RE removal ratios are less than 90% when the RE to precipitant ratio is 1:2 at 600 ℃ whilst the RE Nd content in the salt collected by condensation is reduced to 1.39×10-4 g∙g-1, and its removal ratio is increased to 99.6% with further improved precipitation-distillation processing. Simultaneously, the oxygen and sulfur contents are 8.5×10-5 g∙g-1 and 1.50×10-4 g∙g-1, respectively. Analysis results of XRD, XPS and EDS indicate that the sediment mainly consists of RE sulfide and sulfur oxide.ConclusionsThis study confirms the feasibility of separating RE from waste salt using the sulfide precipitation method and that over 99% RE separation efficiency can be achieved using precipitation-distillation combined treatment. Therefore, this provides a reference method for purifying waste salt and realizing molten salt reuse.

This article summarized the family participatory nursing care in an elderly patient with congenital anomalies of urinary tract undergoing indwelling catheter placement. According to the nursing plan, targeted interventions were carried out. The designed health education program was provided to improve the knowledge and practice skills of primary caregivers, in order to prevent the catheter-associated complications. (本文总结1例老年尿道畸形留置尿管患者的家庭参与式护理体会。通过制定护理目标、护理计划、实施方案且对照护者进行有计划的培训和指导干预, 有效提高了照护者的理论知识、操作技能及执行力, 对预防留置尿管相关并发症起到积极作用。)

BackgroundMolten salt electrochemical separation of spent fuel in molten salt medium is one of the most widely studied technologies in pyroprocessing. It is based on the use of electrolysis to achieve the separation.PurposeThis study aims to investigate the separation of actinides and lanthanides in situ using high-temperature molten salt media.MethodsCyclic voltammetry (CV), square wave voltammetry (SWV), and constant potential electrolysis were employed to study the electrochemical behavior and separation feasibility of UF4 and LnF3 (Ln=Eu, Sm, Yb, La, Ce, and Ho) in FLiBe molten salt. Firstly, the eutectic salt was prepared, followed by the precise measurement and mixing of FLiBe molten salt and UF4 or LnF3 powder in accordance with the desired concentration ratio. Then, the electrochemical behavior of uranium and lanthanide elements in FLiBe molten salt was experimentally studied using electrochemical CV and SWV. Subsequently, the constant potential electrolysis method was employed to achieve the electrochemical deposition of uranium or lanthanide elements. Finally, the feasibility of separating uranium and lanthanide elements in FLiBe molten salt was evaluated through X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS) analysis of the electrolysis products.ResultsExperimental results show that U4+ undergoes two electron transfer reductions on an inert tungsten electrode, namely U4++e-→U3+ and U3++3e-→U0, while Yb3+, Sm3+, and Eu3+ have only one electron transfer reduction, leading to the +2 valence state of Yb2+, Sm2+, and Eu2+ ions, respectively. In addition, La3+, Ce3+, and Ho3+ ions do not exhibit significant electrochemical signals within the electrochemical window of FLiBe molten salt. The findings from XRD and EDS analyses verify that the electrolysis products presented on the W electrode consist of metal U, UF3, and entrain molten salt, with no lanthanide (Ln=Eu, Sm, Yb, La, Ce, and Ho) electrolytic deposition product detected.ConclusionsThe suitable electrolytic separation method developed in this study provides basic data to separate actinides and lanthanides from molten salts.

BackgroundAn electrolyte waste salt containing LiCl and various products is generated during the pyroprocessing of spent nuclear fuel in metal fast reactors. Separating metal impurities from waste salt can purify molten salt, facilitate salt recycling, and reduce the amount of waste salt, achieving waste minimization.PurposeThis study aims to investigate the effects of key factors on the application of the cold finger crystallization method used for removal of Sr and Ba from molten LiCl salt.MethodsA homemade cold finger experimental apparatus was applied to the experimental removal of two alkaline earth metals, Sr and Ba, from molten LiCl salt, and Fluent software was employed to simulate the application of cold finger crystallization equipment during dry reprocessing. The effects of crystal growth time, initial crystallization temperature, and initial SrCl2/BaCl2 concentrations on the removal ratio of the crystalline salt during the process were analyzed.ResultsThe initial temperature of molten salt is a critical factor that influences cold finger separation efficiency. When the initial temperature reaches 660 ℃, the removal efficiency improves. Moreover, when the impurity contents of Sr and Ba in molten salt are lower than 0.55%(w/w), the removal efficiency of the cold finger crystallization method can exceed 80%. Further analysis shows that the removal effects of different parts of molten salt crystals differ. The solvent salt at the top of the molten salt crystal is better, and the removal ratio of the bottom and inner salts is lower. Therefore, the optimal conditions for removing Sr and Ba from LiCl crystalline salt require an initial temperatures of 660~670 ℃, an airflow intensity of 10 L·min-1, and a growth time of 20 min. Under these optimal conditions, the removal ratio can reach 90%.ConclusionsThe proposed approach is feasible for purifying solvent salts from electrolyte waste molten salt via cold finger crystallization. This study provides a reference for purifying waste salt and reusing molten salt.

Diabetes is an independent risk factor for coronary heart disease, and the two are mutually causal in disease progression. Sodium-glucose cotransporter 2 inhibitor is a new oral medicine for the treatment of type 2 diabetes mellitus, which can play a hypoglycemic effect by blocking the reabsorption of glucose by the renal proximal convoluted tubules and increasing the excretion of urine glucose. A large number of studies have confirmed that in addition to hypoglycemic effects, SGLT2 inhibitors can also benefit in the treatment of coronary heart disease. This article mainly reviews the research progress and mechanism of SGLT2 inhibitors in the treatment of T2DM complicated with coronary heart disease.

Two herbal formulas were prepared by combining extracts from Angelica sinensis, Cistanche deserticola, Paeonia lactiflora pall, Fructus sophorae, and Astragalus and assessed for radioprotective efficacy. Fifty-six healthy C57BL/6J mice were γ irradiated at a dose of 4 Gy to establish a radiation injury model. These mice were randomly divided into four groups with equal numbers of males and females: a radiated vehicle control group, a commercial radioprotective extract control group (Hemo-1#), and two experimental groups (Exp-2# and Exp-3#). The vehicle control group was administered an equal volume of distilled water. The other groups were administered different herbal formulas. Body weight and conventional indicators of peripheral blood homeostasis were recorded before and after irradiation. On the first day after irradiation, mice fed herbal extracts experienced a smaller decrease in leukocyte and lymphocyte counts than untreated mice. At 7 days after irradiation, mouse leukocyte, erythrocyte, platelet, and lymphocyte counts displayed slow recovery. The two groups receiving different herbal formulas showed a similar radioprotective effect on body weight and peripheral blood test results than the Hemo-1# group. Our experimental herbal formulas showed radioprotective effects against γ ray-induced damage.

BackgroundIn molten salt reactor, the concentration of oxygen impurities in the molten salt should be strictly controlled to avoid the potential safety risks caused by the reaction of O2- in the carrier salt with UF4 fuel to generated UO2 precipitation.PurposeThis study aims to investigate the evaporation behavior of the main oxygen-containing impuritiy ions in carrier salt at high temperature and low pressure and the influence of process parameters such as temperature, pressure and initial oxygen content of molten salt on the removal of O2- in carrier salt.MethodsThe vacuum distillation method was employed and a vacuum distillation device were used to carried out experimental study of the separation behavior of the main oxygen-containing impurities NO3-, SO42-, PO43- and O2- in the carrier salt during vacuum distillation. The removal mechanism of the above ions was explored, and the specific influence of process conditions on the separation effect of O2- distillation was investigated.ResultsThe results show that the removal ability of oxygen-containing impurities by vacuum distillation is NO3-＞PO43-＞SO42-＞O2-. The removal capacity of O2- increases with the increase of temperature, and the recovered salt with a total oxygen content about 2.40×10-4 g·g-1 salt is obtained at 1 050 ℃. The phenomenon of oxygen with a total oxygen content about 2.50×10-4 g·g-1 salt is observed when the pressure is higher than 40 Pa. The oxygen entrainment is increased during the evaporation of molten salt with the decrease of pressure, and the recovered salt content in the recovered salt continued to decrease with the decrease of the initial content of O2- in the carrier salt, which confirmed the technical feasibility of melting salt multiple distillation to remove oxygen.ConclusionsIt is verified by study shows that vacuum distillation can remove oxygen-containing impurities from carrier salt effectively and achieve the rapid and efficient purification of the carrier salt.

Summary Purpose Methods Results Conclusions Pedicle screw loosening after posterior lumbar fusion is associated with poor bone quality, which often determines screw pull‐out strength, insertion torque, and vertebral body loading characteristics. Magnetic resonance imaging (MRI)‐based vertebral bone quality (VBQ) score were associated with poor bone quality. Current evidence suggests that pedicle bone quality (PBQ) has a greater impact on screw stability. However, the correlation between MRI‐based PBQ score and screw loosening has not been reported.To introduce and evaluate an MRI‐based PBQ score to determine its effectiveness in predicting pedicle screw loosening following lumbar fusion surgery.The retrospective study analyzed 244 patients who underwent posterior lumbar interbody fusion (PLIF) with pedicle screws between December 2017 and December 2021, with CT and MRI imaging before surgery. Data collected included patient demographics and preoperative radiological data. Radiographic screw loosening was measured at 12 months postoperatively. Clinical assessments included pain visual analog scale (VAS) and Oswestry Disability Index (ODI) scores. The PBQ score was measured using MRI scans. We use univariate analysis for preliminary screening of the risk factors of screw loosening. Subsequent analysis involved multivariate logistic regression to identify independent predictive factors for screw loosening. We constructed the receiver operating characteristic (ROC) curve to ascertain the discriminative capacity of the PBQ score. The area under the curve (AUC) quantified its predictive accuracy. Additionally, we evaluated the association between PBQ score and screw loosening using Spearman's correlation analysis.Overall, 244 patients who underwent PLIF with pedicle screw fixation participated in this study, including 35 in the loosening group and 209 in the non‐loosening group. PBQ score in the loosening group was significantly higher than that in the non‐loosening group. On multivariate logistic regression, the higher PBQ score (OR = 8.481, 95% CI: 3.158–22.774; p < 0.001) and the lower mean Hounsfield unit (HU) value of L1‐4 (OR = 0.967, 95% CI 0.951–0.984; p < 0.001) were the variables that significantly predicted screw loosening. The AUC for the PBQ score and HU value were 0.751 (95% CI: 0.673–0.828) and 0.702 (95% CI: 0.612–0.791). The PBQ score optimal cutoff to differentiate patients with loosening and with non‐loosening was calculated as 3.045 with a sensitivity of 85.7% and specificity of 76.9%, while the optimal cutoff of the HU value was 151.5 with a sensitivity of 64.6% and specificity of 89.5%.The association between the PBQ score and the propensity for lumbar pedicle screw loosening was found to be substantial. As a predictive measure, the PBQ score outperformed the HU value in forecasting the likelihood of screw loosening post‐posterior lumbar fusion. [ABSTRACT FROM AUTHOR]