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Objective. To compare the effect of ropivacaine in different concentrations under ultrasound guidance on lumbar muscle nerve blocking in elderly patients undergoing hip replacement surgery. Methods. 60 elderly patients underwent hip replacement in our hospital over a period of April to December of 2019 were equally randomized into control and observation groups, with 30 each. Patients in the control group and observation group received 0.5% and 0.25% ropivacaine to block psoas muscle nerve, respectively. The anesthetic effect of ropivacaine at different concentrations was evaluated by time of sensory block onset and recovery and time of motor block onset and regression, blood pressure, heart rate, visual analogy scale, and postoperative nerve blocking degree. Results. The onset time of sensory and motor block in the observation group was dramatically higher than that in the control group (P < 0.05), while the recovery time of sensory and motor was significantly shorter than that of the control group (P < 0.05). The heart rate in the observation group was notably lower than that in the control group, while the average blood pressure was remarkably higher (P < 0.05). After surgery, the degree of nerve block in the observation group was much lower compared with the control group (P < 0.05), while no marked difference in the visual analogue scale in the control group before and after surgical intervention was observed (P > 0.05). Conclusion. The 0.25% ropivacaine method has distinctive advantages over 0.50% ropivacaine psoas nerve anesthesia in hip replacement surgery in elderly patients. [ABSTRACT FROM AUTHOR]

Biomass has been considered a potential source for preparing carbon materials due to its environmentally friendly and renewable characteristics. In this work, N, S co‐doping activated carbon materials were easily prepared by using rice straw as the carbon source. In addition to being heteroatom source, thiourea can fragment the carbon particles into smaller pieces and create plenty of micropores during the carbonization process. Both theoretical and experimental analyses demonstrate that the incorporation of S and N species into carbon can improve the electrochemical performance of supercapacitors. The as‐made N, S co‐doping activated carbon materials, when used as electrodes, exhibit a high specific capacitance of 256 F g−1 at a current density of 1 A g−1 and maintain a good rate capacitance of 65 % even at a high current density of 50 A g−1. This work may offer valuable guidance for the application of rice straw derived carbon in supercapacitors. [ABSTRACT FROM AUTHOR]

Ni-MOF microbelts have been successfully fabricated by using MXenes as structure-directing agents, which exhibits the excellent electrochemical performance. [Display omitted] • 2D Ni-MOF microbelts are fabricated under the induced effect of MXenes. • 2D Ni-MOF microbelts possess rich redox sites and ensure rapidly electrons moving. • The Ti 3 C 2 T x MXenes can provide additional capacitances to improve the performance. • Excellent performance and good rate stability were obtained for Ti 3 C 2 T x /Ni-MOFs. For the sake of developing new energy storage devices for satisfying the energy needs of the modern society, we herein report an innovative MXene-induced strategy to synthesize Ti 3 C 2 T x MXenes/Ni based metal–organic framework composites (Ti 3 C 2 T x /Ni-MOFs) for high-performance supercapacitors. The two-dimensional (2D) MXenes with oxygen-containing groups on the surface can be used as structure-directing agents to tune the Ni-MOFs into 2D microbelts. The presence of MXenes cannot only improve conductivity of the composite but also provide additional electric double layer capacitance and faradaic pseudocapacitance. The 2D Ni-MOF microbelts can offer rich activity sites for the faradaic redox reactions and shorten the ion transport path. Taking advantages of synergistic effects of Ni-MOF microbelts and Ti 3 C 2 T x MXenes, the prepared Ti 3 C 2 T x /Ni-MOFs electrode shows a good electrochemical performance with 1124 F g−1 at the current density of 1 A g −1 and 62% rate capability at 20 A g −1. This work can offer a new insight to design 2D MOF belts as high-performance electrode materials for supercapacitors. [ABSTRACT FROM AUTHOR]