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2.
Sci Total Environ ; 912: 169592, 2024 Feb 20.
Article in English | MEDLINE | ID: mdl-38154637

ABSTRACT

Fe(II)-induced phase transformations of secondary iron minerals have attracted considerable attention due to their influence on antimony (Sb) mobility. However, Fe(II)-induced natural multicomponent secondary iron mineral (nmSIM) transformations and the corresponding repartitioning of Sb on nmSIM under acidic conditions upon Fe(II) exposure have not been systematically examined. Herein, we investigated the effect of Fe(II) on nmSIM mineralogy and Sb mobility in Sb(V)-bearing nmSIM at pH 3.8 and 5.6 at various Fe(II) concentrations over 15 d. The Sb(V)-bearing nmSIM phase transformation occurred under both strongly and weakly acidic conditions without Fe(II) exposure, while the presence of Fe(II) significantly intensified the transformation, and substantial amounts of intermediary minerals, including jarosite, ferrihydrite, lepidocrocite and fougerite, formed during the initial reaction stage, especially at pH 5.6. X-ray diffraction (XRD) analyses confirmed that goethite and hematite were the primary final-stage transformation products of Sb(V)-bearing nmSIM, regardless of Fe(II) exposure. Throughout the Sb(V)-bearing nmSIM transformation at pH 3.8, Sb release was inversely related to the Fe(II) concentration in the initial stage, and after maximum release was achieved, Sb was gradually repartitioned onto the nmSIM. No Sb repartitioning occurred in the absence of Fe(II) at pH 5.6, but the introduction of Fe(II) suppressed Sb release and improved Sb repartitioning on nmSIM. This transformation was conducive to Sb reimmobilization on Sb(V)-bearing nmSIM due to the structural incorporation of Sb into the highly crystalline goethite and hematite generated by the Sb(V)-bearing nmSIM transformation, and no reduction of Sb(V) occurred. These results imply that Fe(II) can trigger mineralogical changes in Sb(V)-bearing nmSIM and have important impacts on Sb partitioning under acidic conditions. These new insights are essential for assessing the mobility and availability of Sb in acid mine drainage areas.

3.
Chem Commun (Camb) ; 59(96): 14285-14288, 2023 Nov 30.
Article in English | MEDLINE | ID: mdl-37964609

ABSTRACT

The Li5.5PS4.5Cl1.5 electrolyte gains significant attention due to its ultrahigh ionic conductivity and cost-effectiveness in halogen-rich lithium argyrodite solid electrolytes. The conventional synthetic method for obtaining the electrolyte involves mechanical milling followed by post-annealing. However, these synthesis methods typically involve high milling speeds, elevated temperatures, and prolonged durations, resulting in both high energy consumption and potential damage to the electrolyte. In this study, we successfully obtained Li5.5PS4.5Cl1.5 with a high conductivity of 7.92 mS cm-1 using a milling speed of 400 rpm and annealing at 400 °C for 5 hours. When incorporated into a Li4Ti5O12-based all-solid-state battery, this electrolyte demonstrates stable cycling performance across varying temperatures.

4.
Chemosphere ; 327: 138529, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36990360

ABSTRACT

Antimony (Sb) has raised widespread concern because of its negative effects on ecology and human health. The extensive use of antimony-containing products and corresponding Sb mining activities have discharged considerable amounts of anthropogenic Sb into the environment, especially the water environment. Adsorption has been employed as the most effective strategy for Sb sequestration from water; thus, a comprehensive understanding of the adsorption performance, behavior and mechanisms of adsorbents benefits to develop the optimal adsorbent to remove Sb and even drive its practical application. This review presents a holistic analysis of adsorbent species with the ability to remove Sb from water, with a special emphasis on the Sb adsorption behavior of various adsorption materials and their Sb-adsorbent interaction mechanisms. Herein, we summarize research results based on the characteristic properties and Sb affinities of reported adsorbents. Various interactions, including electrostatic interactions, ion exchange, complexation and redox reactions, are fully reviewed. Relevant environmental factors and adsorption models are also discussed to clarify the relevant adsorption processes. Overall, iron-based adsorbents and corresponding composite adsorbents show relatively excellent Sb adsorption performance and have received widespread attention. Sb removal mainly depends on chemical properties of the adsorbent and Sb itself, and complexation is the main driving force for Sb removal, assisted by electrostatic attraction. The future directions of Sb removal by adsorption focus on the shortcomings of current adsorbents; more attention should be given to the practicability of adsorbents and their disposal after use. This review contributes to the development of effective adsorbents for removing Sb and provides an understanding of Sb interfacial processes during Sb transport and the fate of Sb in the water environment.


Subject(s)
Antimony , Water Pollutants, Chemical , Humans , Antimony/analysis , Adsorption , Water Pollutants, Chemical/analysis , Water , Iron/analysis
5.
Nat Commun ; 13(1): 4911, 2022 Aug 20.
Article in English | MEDLINE | ID: mdl-35987982

ABSTRACT

Potassium metal is an appealing alternative to lithium as an alkali metal anode for future electrochemical energy storage systems. However, the use of potassium metal is hindered by the growth of unfavourable deposition (e.g., dendrites) and volume changes upon cycling. To circumvent these issues, we propose the synthesis and application of nitrogen and zinc codoped porous carbon nanofibres that act as potassium metal hosts. This carbonaceous porous material enables rapid potassium infusion (e.g., < 1 s cm-2) with a high potassium content (e.g., 97 wt. %) and low potassium nucleation overpotential (e.g., 15 mV at 0.5 mA cm-2). Experimental and theoretical measurements and analyses demonstrate that the carbon nanofibres induce uniform potassium deposition within its porous network and facilitate a dendrite-free morphology during asymmetric and symmetric cell cycling. Interestingly, when the potassium-infused carbon material is tested as an active negative electrode material in combination with a sulfur-based positive electrode and a nonaqueous electrolyte solution in the coin cell configuration, an average discharge voltage of approximately 1.6 V and a discharge capacity of approximately 470 mA h g-1 after 600 cycles at 500 mA g-1 and 25 °C are achieved.

6.
Comput Math Methods Med ; 2022: 8114073, 2022.
Article in English | MEDLINE | ID: mdl-35799637

ABSTRACT

Background: Diabetic foot gangrene refers to a lesion in which the tissue of the foot or lower extremities of diabetic patients is damaged, and the cause is the infection of peripheral blood vessels and neuropathy caused by diabetes. Objective: To compare the related indexes of blood glucose, inflammation, blood viscosity, and peripheral neuropathy between the nonischemic diabetic foot and ischemic diabetic foot, the same and different characteristics of the two different types of diabetic foot in pathogenesis were discussed and studied. Methods: A total of 122 patients with diabetic foot were selected from the Department of Vascular Medicine, Shanghai Hospital of Integrated Traditional Chinese and Western Medicine, including 61 cases of ischemic type and 61 cases of nonischemic type. The differences in blood glucose, inflammation, blood supply, and peripheral neuropathy between the nonischemic diabetic foot and ischemic diabetic foot were compared to explore their different characteristics. Results: The blood glucose index, inflammatory index, and plasma fibrinogen in patients with nonischemic diabetic foot were significantly higher than those in patients with ischemic diabetic foot (P < 0.05). The patients with ischemic diabetic foot were higher in age and blood lipid index than those with the nonischemic diabetic foot (P < 0.05), while having no significant difference in platelet count, plasma viscosity, hematocrit, and end products of glycation (AGEs). Conclusion: The nonischemic diabetic foot is mainly infective necrosis, and the ischemic type is ischemic necrosis. The former occurs in the middle-aged and elderly with good blood supply between 40 and 60 years old, while the latter occurs in the elderly with the severe vascular disease over 60 years old. The blood glucose level of nonischemic patients is significantly higher than that of ischemic patients, but it has little to do with the course of diabetes.


Subject(s)
Diabetes Mellitus , Diabetic Foot , Adult , Aged , Blood Glucose , China , Diabetic Foot/complications , Gangrene/etiology , Humans , Inflammation , Middle Aged , Necrosis/complications , Tendons
7.
ACS Appl Mater Interfaces ; 14(3): 4179-4185, 2022 Jan 26.
Article in English | MEDLINE | ID: mdl-35038866

ABSTRACT

Chlorine-rich argyrodite-type solid electrolyte Li5.5PS4.5Cl1.5 has been a promising choice for solid-state batteries (SSBs) because of its ultrafast Li-ion conduction. However, the poor air/moisture stability and low electrochemical stability with pristine high-voltage cathodes hinder their applications. Herein, O-substituted Li5.5PS4.5-xOxCl1.5 (x = 0, 0.075, 0.175, and 0.25) solid electrolytes are successfully synthesized. Among them, Li5.5PS4.425O0.075Cl1.5 delivers high ionic conductivity, improved moisture resistance, and enhanced electrochemical stability in higher voltage windows. SSBs using Li5.5PS4.425O0.075Cl1.5 show higher capacities and superior cyclability than those using Li5.5PS4.5Cl1.5 combined with a pristine LiNi0.8Mn0.1Co0.1O2 cathode when operated at a high end-of-charge voltage of 4.5 V (vs Li+/Li0). Moreover, the batteries exhibit outstanding performance in a wide temperature range. This work provides a strategy to modify the inherent drawbacks of sulfide electrolytes, promoting their practical applications.

8.
Microbiol Immunol ; 65(9): 383-391, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34050992

ABSTRACT

Coagulation is a critical pathogenic process in Staphylococcus aureus. Although the agglutination of S. aureus has been studied for a long time, the genes involved in this process are not completely clear. We performed tube agglutination and dynamic turbidimetry tests to identify novel genes involved in reduced plasma coagulation. A total of 15 genes were identified, including coa, clfA, vwbp, saeS, agrA, trpC, spdC, mroQ, cydA, qoxC, sucC, pyrP, menH, threonine aldolase, and truncated transposase for IS1272. The functions of these genes include bicomponent regulation, membrane transport, energy metabolism and biosynthesis, respectively. cydA, spdC, and mroQ genes were further studied by gene knockout and complementation. Results of gene knockout and complementation and real-time-qPCR proved that cydA, spdC, and mroQ genes are necessary for plasma coagulation. Furthermore, the survival ability of 7 day mice decreased significantly when cydA, spdC, and mroQ genes had been knocked out.


Subject(s)
Staphylococcal Infections , Staphylococcus aureus , Agglutination , Animals , Bacterial Proteins/genetics , Coagulase/metabolism , Mice , Staphylococcus aureus/genetics , Staphylococcus aureus/metabolism
9.
ACS Appl Mater Interfaces ; 12(18): 20563-20569, 2020 May 06.
Article in English | MEDLINE | ID: mdl-32286042

ABSTRACT

Room-temperature solid-state sodium batteries have the remarkable potential to simultaneously achieve high safety, high energy density, and low cost. However, their current performance is far below expectations. Through material and interfacial modification based on Na3PS4 solid electrolytes, progress is made toward stable room-temperature solid-state sodium-sulfur (Na-S) batteries. First, the ionic liquid N-butyl-N-methylpyrrolidinium bis(fluorosulfonyl)imide (Pyr14FSI) is employed to modify the anode/electrolyte interface. An overpotential of 0.55 V after 900 h of a symmetrical battery indicates enhanced interfacial stability. A stable in situ solid electrolyte interphase layer is formed at the interface of NaSn alloy and Na3PS4, proved by X-ray photoelectron spectroscopy measurements. Furthermore, selenium-doped sulfurized polyacrylonitrile (Se0.05S0.95@pPAN) is used to boost the ionic and electronic conductivities of the sulfur cathode. As a result, the Na-S battery using a Se0.05S0.95@pPAN cathode and the interfacial modification delivers stable cycle performance and enhanced rate capability.

10.
Medicine (Baltimore) ; 98(44): e17684, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31689789

ABSTRACT

RATIONALE: Pulmonary mucoepidermoid carcinomas (PMECs) of the lung are rare malignant tumors. Despite progresses in examinations, the tumor represents a diagnostic challenge for pathologists and clinical physicians. Here, we present a patient who was eventually diagnosed with PMEC by the bronchoscopic examinations conducted three times. PATIENT CONCERNS: We present the case of a 41-year-old female who was initially diagnosed with pulmonary pleomorphic adenoma (PPA) with a 68 × 82 mm mass and nodules in her lung and eventually diagnosed with PMEC. DIAGNOSES: Based on histopathology, immunohistology, and imaging studies, the patient was diagnosed with PMEC (pT4N2M1). INTERVENTIONS: The patient received first-line systemic chemotherapy regime (gemcitabine combined with carboplatin). OUTCOMES: The patient received 2 cycles of chemotherapy. Based on the response evaluation criteria in solid tumor, she achieved partial response, and the mass was distinctly decreased from 68 × 22 mm to 41 × 17 mm. LESSONS: This case presents a rare PMEC overlapping with PPA, based on histological findings, suggesting that besides imaging studies and laboratory examinations, multiple biopsies and ThinPrep cytology tests are necessary to obtain an accurate diagnosis. The patient showed positive response to chemotherapy.


Subject(s)
Carcinoma, Mucoepidermoid/diagnosis , Carcinoma, Mucoepidermoid/pathology , Lung Neoplasms/diagnosis , Lung Neoplasms/pathology , Adult , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bronchoscopy , Carcinoma, Mucoepidermoid/drug therapy , Female , Humans , Lung Neoplasms/drug therapy
11.
Front Public Health ; 7: 182, 2019.
Article in English | MEDLINE | ID: mdl-31380332

ABSTRACT

Setting: Rifampicin-resistant tuberculosis (RR-TB) in elderly people in Jiangxi Province, China. Objective: To investigate the incidence of RR-TB and risk factors in elderly people within a hospital setting in China. Design: Retrospective cohort study. Methods: A comparative study was performed to analyze RR-TB and rifampicin-susceptible TB (RS-TB). The 15-locus mycobacterial interspersed repetitive unit-variable number of tandem repeats (MIRU-VNTR) method was used to distinguish between relapse and reinfection. Results: Twenty-three recurrent cases occurred in 151 elderly patients with RR-TB, and 24 recurrent cases occurred in 466 elderly patients with RS-TB during this period. TB recurrence was significantly different in the RR-TB and RS-TB groups (OR = 0.35, 95% CI: 0.14-0.88; χ2 = 5.28, P = 0.03). Comparing the risk factors for RR-TB and RS-TB, we found that educational level, age, and pulmonary cavity were inextricably linked to RR-TB in elderly patients. Furthermore, pulmonary cavity, HIV status, and alcohol consumption were associated with recurrence in elderly RR-TB patients. Conclusions: Recurrence is an important source of RR-TB in the elderly population. It is necessary to promptly treat tuberculosis patients, prevent the spread of AIDS, and reduce alcohol intake to control recurrent RR-TB in the elderly population.

12.
J Am Chem Soc ; 141(14): 5640-5644, 2019 Apr 10.
Article in English | MEDLINE | ID: mdl-30912936

ABSTRACT

Sodium superionic conductors are keys to develop high safety and low cost all-solid-state sodium batteries. Among developed sodium ionic conductors, antiperovskite-type ionic conductors have attracted vast interest due to their high structural tolerance and good formability. Herein, we successfully synthesize Na3OBH4 with cubic antiperovskite structure by solid-state reaction from Na2O and NaBH4. Na3OBH4 exhibits ionic conductivity of 4.4 × 10-3 S cm-1 at room temperature (1.1 × 10-2 S cm-1 at 328 K) and activation energy of 0.25 eV. The ionic conductivity is 4 orders of magnitude higher than the existing antiperovskite Na3OX (X = Cl, Br, I). It is shown that such enhancement is not only due to the specific cubic antiperovskite structure of Na3OBH4 but also because of the rotation of BH4 cluster anion. This work deepens the understanding of the antiperovskite structure and the role of cluster anions for superionic conduction.

13.
Nat Commun ; 10(1): 1021, 2019 03 04.
Article in English | MEDLINE | ID: mdl-30833552

ABSTRACT

Sulfurized polyacrylonitrile is suggested to contain Sn (n ≤ 4) and shows good electrochemical performance in carbonate electrolytes for lithium sulfur batteries. However inferior results in ether electrolytes suggest that high solubility of Li2Sn (n ≤ 4) trumps the limited redox conversion, leading to dissolution and shuttling. Here, we introduce a small amount of selenium in sulfurized polyacrylonitrile to accelerate the redox conversion, delivering excellent performance in both carbonate and ether electrolytes, including high reversible capacity (1300 mA h g-1 at 0.2 A g-1), 84% active material utilization and high rate (capacity up to 900 mA h g-1 at 10 A g-1). These cathodes can undergo 800 cycles with nearly 100% Coulombic efficiency and ultralow 0.029% capacity decay per cycle. Polysulfide dissolution is successfully suppressed by enhanced reaction kinetics. This work demonstrates an ether compatible sulfur cathode involving intermediate Li2Sn (n ≤ 4), attractive rate and cycling performance, and a promising solution towards applicable lithium-sulfur batteries.

14.
ACS Appl Mater Interfaces ; 9(18): 15470-15476, 2017 May 10.
Article in English | MEDLINE | ID: mdl-28425696

ABSTRACT

Conversion/alloy-reaction electrode materials promise much higher energy density than the commonly used ones based on intercalation chemistries. However, the low electronic conductivity and, specially, the large volume expansion upon lithiation hinder their practical applications. Here, for the first time, a unique granadilla-inspired structure was designed to prepare the conversion/alloy-reaction anode of carbon coated tin/calcium tin oxide (C@void@Sn/CaSnO3) ternary composite. The granadilla-inspired structure ensures the intimate contact between the Sn/CaSnO3 nanoparticles and the carbon matrix, providing not only conductive networks for electron transport and a short distance for Li+ diffusion but also effective space for the electrode volume expansion toward conversion/alloy reaction. Moreover, the unique structure possesses abundant solid-solid interfaces between the three components as well as solid-liquid interfaces between nanoparticles and electrolyte, contributing to a large percent (58%) of interfacial charge (thus capacity). The integration of alloy-reaction, conversion-reaction, and interfacial lithium storage endows the hybrid electrode with a high capacity and long cycling life, holding great promise for next-generation high-capacity lithium-ion batteries.

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