RESUMO
Implementing fast-charging lithium-ion batteries (LIBs) is severely hindered by the issues of Li plating and poor rate capability for conventional graphite anode. Wadsley-Roth phase TiNb2 O7 is regarded as a promising anode candidate to satisfy the requirements of fast-charging LIBs. However, the unsatisfactory electrochemical kinetics resulting from sluggish ion and electron transfer still limit its wide applications. Herein, an effective strategy is proposed to synchronously improve the ion and electron transfer of TiNb2 O7 by incorporation of oxygen vacancy and N-doped graphene matrix (TNO- x @N-G), which is designed by combination of solution-combustion and electrostatic self-assembly approach. Theoretical calculations demonstrate that Li+ intercalation gives rise to the semi-metallic characteristics of lithiated phases (Liy TNO- x ), leading to the self-accelerated electron transport. Moreover, in situ X-ray diffraction and Raman measurements reveal the highly reversible structural evolution of the TNO- x @N-G during cycling. Consequently, the TNO- x @N-G delivers a higher reversible capacity of 199.0 mAh g-1 and a higher capacity retention of 86.5% than those of pristine TNO (155.8 mAh g-1 , 59.4%) at 10 C after 2000 cycles. Importantly, various electrochemical devices including lithium-ion full battery and hybrid lithium-ion capacitor by using the TNO- x @N-G anode exhibit excellent rate capability and cycling stability, verifying its potential in practical applications.
RESUMO
PURPOSE: We examined the effectiveness of hydrogen rich saline solution on the prevention of testicular damage induced by ischemia/reperfusion in rats. MATERIALS AND METHODS: Male Sprague-Dawley® rats were divided randomly into 4 groups, including group 1-sham operated, group 2-torsion-detorsion, group 3-torsion-detorsion plus saline and group 4-torsion-detorsion plus hydrogen rich saline solution. Testicular torsion was performed by rotating the left testis 720 degrees clockwise for 4 hours. Reperfusion was allowed for 4 hours. Hydrogen rich saline solution (5 ml/kg) was injected intraperitoneally in rats in group 4 15 minutes before the start of detorsion. Rats were sacrificed after 4-hour initiation of detorsion. Left orchiectomy was done for histopathological examination and biochemical assay. RESULTS: The testicular injury score in groups 2 and 3 was significantly lower than in sham operated group 1 but higher in group 4 with hydrogen rich saline than in group 2 with torsion-detorsion. The apoptosis index was significantly increased in groups 2 and 3. Hydrogen rich saline solution treatment significantly decreased the apoptosis index. A significant increase in malondialdehyde and a decrease in superoxide dismutase activity were observed in groups 2 and 3. In group 4 malondialdehyde was significantly lowered and superoxide dismutase activity was significantly improved compared with groups 2 and 3. CONCLUSIONS: Results provide a biochemical and histopathological basis for the action of hydrogen rich saline solution as a therapeutic agent for testicular damage induced by ischemia/reperfusion injury.
