RESUMO
Rechargeable magnesium batteries (RMBs) suffer from low capacity and poor cyclability of cathode materials, which is due to the sluggish Mg2+ diffusion kinetics and large lattice strain. Here, a layer-interweaving mechanism in lamellar cathode to simultaneously facilitate Mg2+ diffusion and release Mg2+ -insertion strain is reported. In the Cu3 V2 O7 (OH)2 ·2H2 O (CVOH) cathode, Mg2+ diffusion highways are generated by the vertical interweaving of CVOH layers and V6 O13 layers that nucleate in CVOH during discharging, which are switchable by Mg2+ insertion/extraction. These highways enhance the Mg2+ diffusion coefficient by three orders of magnitude and release 50% Mg2+ -insertion strain. This enables CVOH to exhibit a high capacity of 262 mAh g-1 at high current density of 250 mA g-1 in aqua, and extremely low capacity loss of 0.0004% per cycle in the activated carbon//CVOH cell. This work inspires designing the magnesiation phase transformation of electrodes to resolve both kinetic and strain issues for high-performance RMBs.
Assuntos
Fontes de Energia Elétrica , Magnésio , EletrodosRESUMO
Rechargeable magnesium-metal batteries (RMMBs) are promising next-generation secondary batteries; however, their development is inhibited by the low capacity and short cycle lifespan of cathodes. Although various strategies have been devised to enhance the Mg2+ migration kinetics and structural stability of cathodes, they fail to improve electronic conductivity, rendering the cathodes incompatible with magnesium-metal anodes. Herein, we propose a dual-defect engineering strategy, namely, the incorporation of Mg2+ pre-intercalation defect (P-Mgd) and oxygen defect (Od), to simultaneously improve the Mg2+ migration kinetics, structural stability, and electronic conductivity of the cathodes of RMMBs. Using lamellar V2O5·nH2O as a demo cathode material, we prepare a cathode comprising Mg0.07V2O5·1.4H2O nanobelts composited with reduced graphene oxide (MVOH/rGO) with P-Mgd and Od. The Od enlarges interlayer spacing, accelerates Mg2+ migration kinetics, and prevents structural collapse, while the P-Mgd stabilizes the lamellar structure and increases electronic conductivity. Consequently, the MVOH/rGO cathode exhibits a high capacity of 197 mAh g-1, and the developed Mg foil//MVOH/rGO full cell demonstrates an incredible lifespan of 850 cycles at 0.1 A g-1, capable of powering a light-emitting diode. The proposed dual-defect engineering strategy provides new insights into developing high-durability, high-capacity cathodes, advancing the practical application of RMMBs, and other new secondary batteries.
RESUMO
Mg-ion batteries (MIBs) are promising next-generation secondary batteries, but suffer from sluggish Mg2+ migration kinetics and structural collapse of the cathode materials. Here, an H2O-Mg2+ waltz-like shuttle mechanism in the lamellar cathode, which is realized by the coordination, adaptive rotation and flipping, and co-migration of lattice H2O molecules with inserted Mg2+, leading to the fast Mg2+ migration kinetics, is reported; after Mg2+ extraction, the lattice H2O molecules rearrange to stabilize the lamellar structure, eliminating structural collapse of the cathode. Consequently, the demo cathode of Mg0.75V10O24·nH2O (MVOH) exhibits a high capacity of 350 mAh g-1 at a current density of 50 mA g-1 and maintains a capacity of 70 mAh g-1 at 4 A g-1. The full aqueous MIB based on MVOH delivers an ultralong lifespan of 5000 cycles The reported waltz-like shuttle mechanism of lattice H2O provides a novel strategy to develop high-performance cathodes for MIBs as well as other multivalent-ion batteries.
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OBJECTIVE: To investigate the expressions of GRα mRNA and GRß mRNA in the peripheral blood mononuclear cells (PBMCs) of systemic lupus erythematosus (SLE) patients, in order to reveal the role of GR mRNA in the pathogenesis of SLE and analyze the relationship between GR mRNA and SLEDAI score, dsDNA, cardiovascular involvement. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) technique was applied to semiquantitatively analyze GRα mRNA and GRß mRNA expressions in 104 SLE patients and 56 volunteers. RESULTS: The level of GRα mRNA was lower in the SLE group (the relative level was 1.24±0.97)than in the control group (the relative level was 2.31±1.42, P<0.05), and the level of GRß mRNA was higher in the SLE group(the relative level was 0.61±1.23) than in the control group(the relative level was 0.18±0.21, P<0.05). The level of GRα was lower in the active group (the relative level was 0.68±0.40) than in the inactive group(the relative level was 1.65±1.06, P<0.01), but the level of GRß was higher in the active group(the relative level was 0.88±1.56) than in the inactive group(the relative level was 0.24±0.23, P<0.01); GRα mRNA was related negatively to the SLEDAI score and dsDNA, but GRß mRNA was related positively to the SLEDAI score and dsDNA(P<0.01).The level of GRα mRNA was lower in the dsDNA positive group(the relative level was 0.89±0.66) than in the dsDNA negative group (the level was 1.54±1.10), the level of GRß mRNA was higher in the dsDNA positive group (the relative level was 0.95±1.60) than in the dsDNA negative group (the relative level was 0.22±0.21). The level of GRß mRNA and the value of GRß mRNA/ GRα mRNA was obviously higher in the SLE group with cardiac involvement (the relative level was 1.02 ±1.76, the valve of GRß / GRα was 1.10±2.02)than in the SLE group without cardiac involvement (the relative level was 0.28±0.31, the valve of GRß / GRα was 0.32±0.32, P<0.05), and the level of GRα mRNA wasn't significant in the two groups (P>0.05). CONCLUSION: The levels of GRα mRNA and GRß mRNA maybe play an important role in the pathogenesis of SLE. And the levels of GRα mRNA and GRß mRNA are related to the activity of SLE. The level of GRß mRNA and the value of GRß mRNA/ GRα mRNA are related with cardiovascular involvement in SLE.
Assuntos
Leucócitos Mononucleares/metabolismo , Lúpus Eritematoso Sistêmico/imunologia , Receptores de Glucocorticoides/metabolismo , Adulto , Feminino , Cardiopatias/etiologia , Humanos , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/fisiopatologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Glucocorticoides/genética , Adulto JovemRESUMO
The aim of this study was to explore the correlation of salazosulfamide efficacy on ankylosing spondylitis and N-acetyltransferase 1 (NAT1) gene polymorphism. Thirty-two patients with ankylosing spondylitis were recruited in the experimental group and 36 normal individuals were recruited to the control group. The experimental group received 8.0 mg of salazosulfamide (MTX) per week and the control group received isodose of normal saline. Twenty-six patients in the experimental group responded to the salazosulfamide treatment and 6 did not show response. Morning stiffness time of patients in the experimental group who responded to salazosulfamide was significantly lower than that of patients with no reaction to salazosulfamide, and similar to patients in the control group. The average tender joint count of patients in the experimental group that responded to salazosulfamide was lower than in patients with no response to treatment, and similar to patients in the control group. NAT1 gene sequencing determined that the patients sensitive to salazosulfamide treatment manifested as AA/AG at 263 locus, whereas patients not sensitive to salazosulfamide were GG. NAT1 expression was comparable between the different genotypes at the mRNA level. However, there was a significant difference of NAT1 protein between groups. Overall, salazosulfamide demonstrates curative activity for ankylosing spondylitis and we believe that NAT1 AA/GG genotype at 263 locus can promote salazosulfamide effectiveness on ankylosing spondylitis.