RESUMO
Ultrahigh-capacity silicon (Si) anodes are essential for the escalating energy demands driven by the booming e-transportation and energy storage field. However, their practical applications are strictly hampered by their intrinsically low electroconductivity, sluggish Li-ion diffusion, and undesirably large volume change. Herein, a high-performance Si anode, comprised of a modulated soft/hard coating of polyethylene glycol (PEG) (as Li-ion conductor) and polyaniline (PANI) (as electron conductor) on the surface of Si nanoparticles (NPs) through H-bonding network, is introduced. In this design, the abundant âOH groups of soft PEG allow it to uniformly cover Si NPs while the hard PANI binds to PEG through its âNâH group, thus constructing a tight connectin between Si and PEG-PANI (PP). Consequently, the elastic PP allows Si@PP to accommodate the huge volume expansion while possessing fine electronic/ionic conductivity. Therefore, the Si@PP anode exhibits a high initial Coulombic efficiency of 90.5% and a stable capacity of 1871 mAh g-1 after 100 cycles at 1 A g-1 with a retention of 85.7%. Additionally, the Si@PP anode also demonstrates a high areal capacity of 3.01 mAh cm-2 after 100 cycles at 0.5 A g-1 . This work reveals a scalable interface design of multi-layer multifunctional coatings for high-performance electrode materials in next-generation Li-ion batteries.
RESUMO
We reported a case of a 68-year-old man who presented with recurrent fever and multiorgan dysfunction. His significantly elevated procalcitonin and C-reactive protein levels indicated recurrent sepsis. However, no focus of infection and no pathogens were identified through a variety of examinations and tests. Although the increase of creatine kinase was less than five times the upper limit of normal value, the diagnosis of rhabdomyolysis secondary to adrenal insufficiency resulting from primary empty sella syndrome was finally made, as supported by serum myoglobin elevation, serum cortisol, and adrenocorticotropic hormone deficiency, bilateral adrenal atrophy on computed tomography, and empty sella on magnetic resonance imaging. After the glucocorticoid replacement treatment, the patient's myoglobin gradually returned to normal range, and his condition continued to improve. Rhabdomyolysis resulting from a rare cause may be misdiagnosed as sepsis in patients who present with increased procalcitonin levels.
Assuntos
Síndrome da Sela Vazia , Rabdomiólise , Sepse , Masculino , Humanos , Idoso , Síndrome da Sela Vazia/complicações , Síndrome da Sela Vazia/diagnóstico , Mioglobina , Pró-Calcitonina , Rabdomiólise/diagnóstico , Rabdomiólise/etiologia , Sepse/diagnóstico , Sepse/complicações , Erros de DiagnósticoRESUMO
Layered vanadium-based oxides are the promising cathode materials for aqueous zinc-ion batteries (AZIBs). Herein, an in situ electrochemical strategy that can effectively regulate the interlayer distance of layered NH4 V4 O10 quantitatively is proposed and a close relationship between the optimal performances with interlayer space is revealed. Specifically, via increasing the cutoff voltage from 1.4, 1.6 to 1.8 V, the interlayer space of NH4 V4 O10 can be well-controlled and enlarged to 10.21, 11.86, and 12.08 Å, respectively, much larger than the pristine one (9.5 Å). Among them, the cathode being charging to 1.6 V (NH4 V4 O10 -C1.6), demonstrates the best Zn2+ storage performances including high capacity of 223 mA h g-1 at 10 A g-1 and long-term stability with capacity retention of 97.5% over 1000 cycles. Such superior performances can be attributed to a good balance among active redox sites, charge transfer kinetics, and crystal structure stability, enabled by careful control of the interlayer space. Moreover, NH4 V4 O10 -C1.6 delivers NH4 + storage performances whose capacity reaches 296 mA h g-1 at 0.1 A g-1 and lifespan lasts over 3000 cycles at 5 A g-1 . This study provides new insights into understand the limitation of interlayer space for ion storage in aqueous media and guides exploration of high-performance cathode materials.
RESUMO
Zinc metal is emerging as the promising anode for aqueous Zn-ion batteries. However, corrosion and undesirable Zn dendrite growth limit their practical application in the large-scale energy storage area. Herein, a mountain-valley micro/nanostructure is successfully fabricated on the surface of the Zn anode via a femtosecond-laser filament texturing (FsLFT) technique. Beneficial from the large surface area and spontaneously generated ZnO coating layer, the FsLFT-Zn electrode demonstrates a slow corrosion rate with a current density of 0.62 mA cm-2 and a stable cycle life over 3000 h under 1 mA cm-2, superior to the original Zn anode. Simulation of the electric fields reveals that the enlarged surface area is responsible for the outstanding performance of the FsLFT-Zn electrode. This study not only proposes a novel strategy to suppress dendrite growth toward highly stable AZIBs but also opens a new avenue to solve similar issues in other metal batteries.
RESUMO
Layered transition metal oxides are ideal Na+/K+ host materials due to their high theoretical capacities and appropriate working potentials, and the pursuit of cost-effective and environmentally friendly alternatives with high energy density and structural stability has remained a hot topic. Herein, we design and synthesize a low-cost and zero-strain cathode material, P3-type K0.4Fe0.1Mn0.8Ti0.1O2, which demonstrates superior properties for both potassium and sodium storage. The cathode delivers a reversible potassium storage capacity of 117 mA h g-1 at 20 mA g-1 and a fast rate capability of 71 mA h g-1 at 1000 mA g-1. In situ X-ray diffraction reveals a solid-solution transition with a negligible volume change of 0.5% upon K+ insertion/deinsertion that ensures long cycling stability over 300 cycles. When the material is employed for sodium storage, a spontaneous ion-exchange process with Na+-containing electrolytes occurs. Thanks to the positive effects of the remaining K+ ions that protect the layered structure from collapse as well as expand the interlayer structure, and the resulting K0.12Na0.28Fe0.1Mn0.8Ti0.1O2 demonstrates a high sodium storage capacity of 160 mA h g-1 and superior cycling stability with capacity retention of 81% after 300 cycles as well as fast kinetics.
RESUMO
INTRODUCTION: Xylazine, a type of α2-adrenoceptors, is a commonly used drug in veterinary medicine. Xylazine-induced changes in the content of amino acid neurotransmitters - glycine (Gly) and aspartic acid (Asp), in different brain regions and neurons were studied. MATERIAL AND METHODS: Wistar rats were administered 50 mg/kg or 70 mg/kg of xylazine by intraperitoneal injection. In addition, in vitro experiments were conducted, in which neurons were treated with 15 µg/mL, 25 µg/mL, 35µg/mL, and 45 µg/mL of xylazine. Test methods were based on the enzyme-linked immunosorbent assays (ELISA). RESULTS: During anaesthesia, Asp levels in each brain area were significantly lower compared to the control group. Except for the cerebrum, levels of Gly in other brain areas were significantly increased during the anaesthesia period. In vitro, xylazine-related neuron secretion of Gly increased significantly compared to the control group at 60 min and 90 min. Moreover, xylazine caused a significant decrease in the levels of Asp secreted by neurons at 20 min, but gradually returned to the level of the control group. CONCLUSION: The data showed that during anaesthesia the overall levels of Asp decreased and overall levels of Gly increased. In addition, the inhibitory effect of xylazine on Asp and the promotion of Gly were dose-dependent. Our data showed that different effects of xylazine on excitatory and inhibitory neurotransmitters provided a theoretical basis for the mechanism of xylazine activity in clinical anaesthesia.