Potassium-ion batteries(PIBs)offer a cost-effective and resource-abundant solution for large-scale energy storage.However,the progress of PIBs is impeded by the lack of high-capacity,long-life,and fast-kinetics anode ...Potassium-ion batteries(PIBs)offer a cost-effective and resource-abundant solution for large-scale energy storage.However,the progress of PIBs is impeded by the lack of high-capacity,long-life,and fast-kinetics anode electrode materials.Here,we propose a dual synergic optimization strategy to enhance the K^(+)storage stability and reaction kinetics of Bi_(2)S_(3) through two-dimensional compositing and cation doping.Externally,Bi_(2)S_(3) nanoparticles are loaded onto the surface of three-dimensional interconnected Ti_(3)C_(2)T_(x) nanosheets to stabilize the electrode structure.Internally,Cu^(2+)doping acts as active sites to accelerate K^(+)storage kinetics.Various theoretical simulations and ex situ techniques are used to elucidate the external–internal dual synergism.During discharge,Ti_(3)C_(2)T_(x) and Cu^(2+)collaboratively facilitate K+intercalation.Subsequently,Cu^(2+)doping primarily promotes the fracture of Bi2S3 bonds,facilitating a conversion reaction.Throughout cycling,the Ti_(3)C_(2)T_(x) composite structure and Cu^(2+)doping sustain functionality.The resulting Cu^(2+)-doped Bi2S3 anchored on Ti_(3)C_(2)T_(x)(C-BT)shows excellent rate capability(600 mAh g^(-1) at 0.1 A g^(–1);105 mAh g^(-1) at 5.0 A g^(-1))and cycling performance(91 mAh g^(-1) at 5.0 A g^(-1) after 1000 cycles)in half cells and a high energy density(179 Wh kg–1)in full cells.展开更多
Two-dimensional transition metal carbides and nitrides(MXene)have emerged as promising candidates for microwave absorption(MA)materials.However,they also have some drawbacks,such as poor impedance matching,high self-s...Two-dimensional transition metal carbides and nitrides(MXene)have emerged as promising candidates for microwave absorption(MA)materials.However,they also have some drawbacks,such as poor impedance matching,high self-stacking tendency,and high density.To tackle these challenges,MXene nanosheets were incorporated into polyacrylonitrile(PAN)nanofibers and subsequently assembled into a three-dimensional(3D)network structure through PAN carbonization,yielding MXene/C aerogels.The 3D network effectively extends the path of microcurrent transmission,leading to enhanced conductive loss of electromagnetic(EM)waves.Moreover,the aerogel’s rich pore structure significantly improves the impedance matching while effectively reducing the density of the MXenebased absorbers.EM parameter analysis shows that the MXene/C aerogels exhibit a minimum reflection loss(RL_(min))value of−53.02 dB(f=4.44 GHz,t=3.8 mm),and an effective absorption bandwidth(EAB)of 5.3 GHz(t=2.4 mm,7.44–12.72 GHz).Radar cross-sectional(RCS)simulations were employed to assess the radar stealth effect of the aerogels,revealing that the maximum RCS reduction value of the perfect electric conductor covered by the MXene/C aerogel reaches 12.02 dB m^(2).In addition to the MA performance,the MXene/C aerogel also demonstrates good thermal insulation performance,and a 5-mm-thick aerogel can generate a temperature gradient of over 30℃ at 82℃.This study provides a feasible design approach for creating lightweight,efficient,and multifunctional MXene-based MA materials.展开更多
Exploiting high-rate anode materials with fast K+diffusion is intriguing for the development of advanced potassium-ion batteries(KIBs)but remains unrealized.Here,heterostructure engineering is proposed to construct th...Exploiting high-rate anode materials with fast K+diffusion is intriguing for the development of advanced potassium-ion batteries(KIBs)but remains unrealized.Here,heterostructure engineering is proposed to construct the dual transition metal tellurides(CoTe_(2)/ZnTe),which are anchored onto two-dimensional(2D)Ti_(3)C_(2)T_(x)MXene nanosheets.Various theoretical modeling and experimental findings reveal that heterostructure engineering can regulate the electronic structures of CoTe_(2)/ZnTe interfaces,improving K+diffusion and adsorption.In addition,the different work functions between CoTe_(2)/ZnTe induce a robust built-in electric field at the CoTe_(2)/ZnTe interface,providing a strong driving force to facilitate charge transport.Moreover,the conductive and elastic Ti_(3)C_(2)T_(x)can effectively promote electrode conductivity and alleviate the volume change of CoTe_(2)/ZnTe heterostructures upon cycling.Owing to these merits,the resulting CoTe_(2)/ZnTe/Ti_(3)C_(2)T_(x)(CZT)exhibit excellent rate capability(137.0 mAh g^(-1)at 10 A g^(-1))and cycling stability(175.3 mAh g^(-1)after 4000 cycles at 3.0 A g^(-1),with a high capacity retention of 89.4%).More impressively,the CZT-based full cells demonstrate high energy density(220.2 Wh kg^(-1))and power density(837.2 W kg^(-1)).This work provides a general and effective strategy by integrating heterostructure engineering and 2D material nanocompositing for designing advanced high-rate anode materials for next-generation KIBs.展开更多
AIMTo retrospectively evaluate the safety and feasibility of a new modified laparoscopic Sugarbaker repair in patients with parastomal hernias.METHODSA retrospective study was performed to analyze eight patients who u...AIMTo retrospectively evaluate the safety and feasibility of a new modified laparoscopic Sugarbaker repair in patients with parastomal hernias.METHODSA retrospective study was performed to analyze eight patients who underwent parastomal hernia repair between June 2016 and January 2018. All of these patients received modified laparoscopic Sugarbakerhernia repair treatment. This modifed technique included an innovative three-point anchoring and complete su-turing technique to fix the mesh. All procedures were performed by a skilled hernia surgeon. Demographic data and perioperative outcomes were collected to eva-luate the safety and effcacy of this modifed technique.RESULTSOf these eight patients, two had concomitant incisional hernias. All the hernias were repaired by the modifed laparoscopic Sugarbaker technique with no conversion to laparotomy. Three patients had in-situ reconstruc-tion of intestinal stoma. The median mesh size was 300 cm2, and the mean operative time was 205.6 min. The mean postoperative hospitalization time was 10.4 d, with a median pain score of 1 （visual analog scale method） at postoperative day 1. Two patientsdeveloped postoperative complications. One patient had a pocket of effusion surrounding the biologic mesh, and one patient experienced an infection around the reconstructed stoma. Both patients recovered after conservative management. There was no recurrence during the follow-up period （6-22 mo, average 13 mo）.CONCLUSIONThe modifed laparoscopic Sugarbaker repair could fx the mesh reliably with mild postoperative pain and a low recurrence rate. The technique is safe and feasible for parastomal hernias.展开更多
基金This work received financial support from the National Natural Science Foundation of China(Grant Nos.U23A20574,52250010,and 52201242)the 261 Project MIIT,the Young Elite Scientists Sponsorship Program by CAST(Grant No.2021QNRC001)+1 种基金the Fundamental Research Funds for the Central Universities(Grant No.2242022R40018)the Jiangsu Funding Program for Excellent Postdoctoral Talent(Grant No.2022ZB75).
文摘Potassium-ion batteries(PIBs)offer a cost-effective and resource-abundant solution for large-scale energy storage.However,the progress of PIBs is impeded by the lack of high-capacity,long-life,and fast-kinetics anode electrode materials.Here,we propose a dual synergic optimization strategy to enhance the K^(+)storage stability and reaction kinetics of Bi_(2)S_(3) through two-dimensional compositing and cation doping.Externally,Bi_(2)S_(3) nanoparticles are loaded onto the surface of three-dimensional interconnected Ti_(3)C_(2)T_(x) nanosheets to stabilize the electrode structure.Internally,Cu^(2+)doping acts as active sites to accelerate K^(+)storage kinetics.Various theoretical simulations and ex situ techniques are used to elucidate the external–internal dual synergism.During discharge,Ti_(3)C_(2)T_(x) and Cu^(2+)collaboratively facilitate K+intercalation.Subsequently,Cu^(2+)doping primarily promotes the fracture of Bi2S3 bonds,facilitating a conversion reaction.Throughout cycling,the Ti_(3)C_(2)T_(x) composite structure and Cu^(2+)doping sustain functionality.The resulting Cu^(2+)-doped Bi2S3 anchored on Ti_(3)C_(2)T_(x)(C-BT)shows excellent rate capability(600 mAh g^(-1) at 0.1 A g^(–1);105 mAh g^(-1) at 5.0 A g^(-1))and cycling performance(91 mAh g^(-1) at 5.0 A g^(-1) after 1000 cycles)in half cells and a high energy density(179 Wh kg–1)in full cells.
基金supported by the National Natural Science Foundation of China(52171033)the Natural Science Foundation of Jiangsu Province(No.BK20201283).
文摘Two-dimensional transition metal carbides and nitrides(MXene)have emerged as promising candidates for microwave absorption(MA)materials.However,they also have some drawbacks,such as poor impedance matching,high self-stacking tendency,and high density.To tackle these challenges,MXene nanosheets were incorporated into polyacrylonitrile(PAN)nanofibers and subsequently assembled into a three-dimensional(3D)network structure through PAN carbonization,yielding MXene/C aerogels.The 3D network effectively extends the path of microcurrent transmission,leading to enhanced conductive loss of electromagnetic(EM)waves.Moreover,the aerogel’s rich pore structure significantly improves the impedance matching while effectively reducing the density of the MXenebased absorbers.EM parameter analysis shows that the MXene/C aerogels exhibit a minimum reflection loss(RL_(min))value of−53.02 dB(f=4.44 GHz,t=3.8 mm),and an effective absorption bandwidth(EAB)of 5.3 GHz(t=2.4 mm,7.44–12.72 GHz).Radar cross-sectional(RCS)simulations were employed to assess the radar stealth effect of the aerogels,revealing that the maximum RCS reduction value of the perfect electric conductor covered by the MXene/C aerogel reaches 12.02 dB m^(2).In addition to the MA performance,the MXene/C aerogel also demonstrates good thermal insulation performance,and a 5-mm-thick aerogel can generate a temperature gradient of over 30℃ at 82℃.This study provides a feasible design approach for creating lightweight,efficient,and multifunctional MXene-based MA materials.
基金The authors thank the financial support from the National Natural Science Foundation of China(No.52201242 and 52250010)Natural Science Foundation of Jiangsu Province(No.BK20200386)+1 种基金Young Elite Scientists Sponsorship Program by CAST(No.2021QNRC001)the Fundamental Research Funds for the Central Universities(No.2242022R40018).
文摘Exploiting high-rate anode materials with fast K+diffusion is intriguing for the development of advanced potassium-ion batteries(KIBs)but remains unrealized.Here,heterostructure engineering is proposed to construct the dual transition metal tellurides(CoTe_(2)/ZnTe),which are anchored onto two-dimensional(2D)Ti_(3)C_(2)T_(x)MXene nanosheets.Various theoretical modeling and experimental findings reveal that heterostructure engineering can regulate the electronic structures of CoTe_(2)/ZnTe interfaces,improving K+diffusion and adsorption.In addition,the different work functions between CoTe_(2)/ZnTe induce a robust built-in electric field at the CoTe_(2)/ZnTe interface,providing a strong driving force to facilitate charge transport.Moreover,the conductive and elastic Ti_(3)C_(2)T_(x)can effectively promote electrode conductivity and alleviate the volume change of CoTe_(2)/ZnTe heterostructures upon cycling.Owing to these merits,the resulting CoTe_(2)/ZnTe/Ti_(3)C_(2)T_(x)(CZT)exhibit excellent rate capability(137.0 mAh g^(-1)at 10 A g^(-1))and cycling stability(175.3 mAh g^(-1)after 4000 cycles at 3.0 A g^(-1),with a high capacity retention of 89.4%).More impressively,the CZT-based full cells demonstrate high energy density(220.2 Wh kg^(-1))and power density(837.2 W kg^(-1)).This work provides a general and effective strategy by integrating heterostructure engineering and 2D material nanocompositing for designing advanced high-rate anode materials for next-generation KIBs.
文摘AIMTo retrospectively evaluate the safety and feasibility of a new modified laparoscopic Sugarbaker repair in patients with parastomal hernias.METHODSA retrospective study was performed to analyze eight patients who underwent parastomal hernia repair between June 2016 and January 2018. All of these patients received modified laparoscopic Sugarbakerhernia repair treatment. This modifed technique included an innovative three-point anchoring and complete su-turing technique to fix the mesh. All procedures were performed by a skilled hernia surgeon. Demographic data and perioperative outcomes were collected to eva-luate the safety and effcacy of this modifed technique.RESULTSOf these eight patients, two had concomitant incisional hernias. All the hernias were repaired by the modifed laparoscopic Sugarbaker technique with no conversion to laparotomy. Three patients had in-situ reconstruc-tion of intestinal stoma. The median mesh size was 300 cm2, and the mean operative time was 205.6 min. The mean postoperative hospitalization time was 10.4 d, with a median pain score of 1 （visual analog scale method） at postoperative day 1. Two patientsdeveloped postoperative complications. One patient had a pocket of effusion surrounding the biologic mesh, and one patient experienced an infection around the reconstructed stoma. Both patients recovered after conservative management. There was no recurrence during the follow-up period （6-22 mo, average 13 mo）.CONCLUSIONThe modifed laparoscopic Sugarbaker repair could fx the mesh reliably with mild postoperative pain and a low recurrence rate. The technique is safe and feasible for parastomal hernias.
