High-efficiency selective leaching of valuable metals from spent lithium-ion batteries: Effects of Na2S2O8 on the leaching of metals.

A new method was presented for the high-efficiency selective leaching of Li and the efficient recovery of transition metals (TMs) from the cathode materials of spent lithium-ion batteries (spent LIBs). Selective leaching of Li was achieved by carbothermic reduction roasting and leaching with Na2S2O8. After reduction roasting, high-valence TMs were reduced to low-valence metals or metal oxides, and Li was converted to Li2CO3. Then Na2S2O8 solution selectively extracted 94.15% of Li from roasted product with leaching selectivity of more than 99%. At last, TMs were leached with H2SO4 without adding reductant with the leaching efficiency of metals all exceeding 99%. Na2S2O8 added during the leaching process destroyed the agglomerated structure of the roasted product to open the way Li entered the solution. Under the oxidative environment of Na2S2O8 solution, TMs would not be extracted. At the same time, it helped to regulate the phase of TMs and improved the extraction of TMs. Furthermore, the phase transformation mechanism of roasting and leaching was discussed through thermodynamic analysis, XRD, XPS, and SEM-EDS. This process not only realized the selectively comprehensive recycling of valuable metals in spent LIBs cathode materials; but also followed the principle of green chemistry.

Impact of Cerebrospinal Fluid Sample Handling on Cytokine Detection Results.

OBJECTIVE: To investigate the impact of different treatment methods on cerebrospinal fluid (CSF) cytokine detection. METHODS: CSF samples were collected from 25 patients. The levels of IL-6, IL-10, IFN-γ, and IL-2 were measured after CSF was stored at room temperature (25°C) or 4°C for 6, 12, and 24 hrs. The CSF was frozen at -80°C, thawed at room temperature for 1 hr every 8 hrs and then frozen. This process was repeated three times in a row, and then cytokine levels in CSF were detected again. RESULTS: The four cytokines were stable when the CSF was kept at room temperature for 6 hrs. After 12 hrs of storage, the levels of the four cytokines decreased, and the changes in IL-6 and IL-10 levels were statistically significant. After 24 hrs of storage, the levels of the four cytokines were further reduced, and the changes were statistically significant. Cytokines were stable when CSF was stored at 4°C, and only IL-10 exhibited statistically significant changes when stored for 24 hrs. IL-6, IL-10 IFN-γ, and IL-2 were stable in CSF samples after three freeze-thaw cycles. CONCLUSION: The stability of CSF cytokines is poor after storage at room temperature and good after storage at 4°C. Therefore, cytokine detection should be carried out after CSF collection as often as possible. If the detection cannot be done quickly enough, the specimens should be stored in cold storage for no more than 24 hrs.

Topical Application of Methyl Nicotinate Solution Enhances Peripheral Blood Collection.

OBJECTIVE: The purpose of this study was to investigate whether local application of methyl nicotinate solution can change the content and proportion of blood cells in peripheral blood samples and to determine whether this treatment is a safe and reliable method for improving peripheral blood collection. METHODS: Routine blood analysis and flow cytometry were used to analyze the contents and proportions of blood cells and T lymphocyte subsets in peripheral blood samples. Experimental blood specimens were collected from earlobes treated with different concentrations of methyl nicotinate solution, and the control group consisted of blood specimens collected from untreated earlobes. RESULTS: The blood flow in the earlobe was significantly increased after methyl nicotinate solution stimulation, especially when the methyl nicotinate solution concentration was greater than 10-4 mol/L. There were no significant changes in the proportions of white blood cells, red blood cells, platelets, neutrophils, eosinophils, basophils, monocytes, or lymphocytes in the peripheral blood obtained from earlobes treated with methyl nicotinate solution. The proportion of T lymphocytes increased in the experimental group, but this difference was not significant. CONCLUSION: Local application of methyl nicotinate solution is a feasible method for improving peripheral blood collection, especially for patients with venous blood collection phobia or an inability to provide venous blood samples.

Changes and significance of plasma fibrinogen gamma-chain concentration in preeclampsia patients.

OBJECTIVE: To investigate the plasma fibrinogen gamma-chain concentration in preeclampsia patients and explore its value in preeclampsia prediction and auxiliary diagnosis. METHODS: Follow-up of pregnant women who regularly attended perinatal care at two hospitals in China was performed, and clinical data and plasma samples were collected at each examination until delivery. The gamma-chain concentration was detected by Western blotting, and Quantity One Software was used for gamma-chain grayscale value measurements. RESULTS: Forty-two patients with preeclampsia and 42 control patients completed the follow-up. In the control group, the gamma-chain concentration at 32 weeks of gestation was higher than that at 20 weeks of gestation, but the difference was not statistically significant (p > 0.05). In the experimental group, the gamma-chain concentration at preeclampsia diagnosis was significantly higher than that at 20 weeks of gestation (p < 0.05). Compared with the control group, the gamma-chain concentration was higher at 20 weeks of gestation in the experimental group, but the difference was not statistically significant. However, at 32 weeks of gestation and at the time of diagnosis, the gamma-chain concentration in the experimental group was significantly higher than that in the control group (p < 0.05). At 32 weeks of gestation and at the time of diagnosis, the AUCs from ROC curve analysis of plasma fibrinogen gamma-chain concentrations were 0.64 and 0.71, respectively. CONCLUSION: Plasma fibrinogen synthesis and degradation were disrupted in preeclampsia patients before and after diagnosis, and gamma-chain concentration was significantly increased. Plasma fibrinogen gamma chain may be of some value in preeclampsia prediction and auxiliary diagnosis.