Effectively controlling deep non-compressible bleeding remains a major challenge.In this study,by mimicking nanofiber structure and netting blood cells function of fibrin network in blood clots,we develop a novel bioi...Effectively controlling deep non-compressible bleeding remains a major challenge.In this study,by mimicking nanofiber structure and netting blood cells function of fibrin network in blood clots,we develop a novel bioinspired quaternized chitosan nanofiber sponge with distinct blood cells filtration and blood plasma absorption bifunction for rapid hemostasis.The quaternized chitosan nanofiber sponge possesses a unique gradient pore structure with small pores on the outer surface and large pores in the inner part.The outer small pores effectively capture blood cells with a filtration efficiency as high as 91.7%,while the inner large pores endow with an ultrahigh liquid absorption capacity(93 g/g),surpassing previously reported literature records.The quaternized chitosan nanofiber sponge demonstrates a hemostasis time 2.5 times faster than that of the commercial gelatin®hemostatic sponge when treating the rat liver defect bleeding(noncompressible hemorrhage model).When applied to the rabbit arterial injury bleeding(lethal arterial hemorrhage model),the bioinspired nanofiber sponge achieves bleeding control within only 61.6 s,while both commercial gelatin®hemostatic sponge and commercial collagen®hemostatic sponge fail to stop bleeding even after 240 s.This bioinspired nanofiber sponge derived from the physiological coagulation process may hold great potential for pre-hospital and battlefield first aid.展开更多
Extraction of silica from fly ash to produce mesoporous silica materials is one of the most important utilization approaches.Mesoporous silica could not be synthesized on a large-scale by conventional sol-gel method.I...Extraction of silica from fly ash to produce mesoporous silica materials is one of the most important utilization approaches.Mesoporous silica could not be synthesized on a large-scale by conventional sol-gel method.In this paper,facile preparation of mesoporous silica with controllable pore structure from fly ash by the template-free process via two steps of mineral phase transformation and selective acid etching was proposed.The influence of crystalline structure and acid etching degree on structure of as-synthesized mesoporous silica materials was revealed,as well as mechanism of crystalline structure transformation and pore structure formation.The results show that mullite and quartz could be transformed into acid-soluble kaliophilite when fly ash reacted with K_(2)CO_(3)at temperature of 800-1100℃.The hexagonal kaliophilite would be transformed into orthorhombic KAlSiO_(4)-O1 phase when the temperature is controlled at 1100℃.Mesoporous silica with specific surface area of 475.93 m^(2)/g and 642.57 m^(2)/g could be synthesized from activated fly ash with kaliophilite and KAlSiO_(4)-O1 phase crystalline structure.By controlling the degree of acid etching,mesoporous silica materials with different pore structures can be obtained.This paper provides a cost-effective and large-scale process for the preparation of mesoporous silica materials with controllable pore structure from solid waste fly ash.展开更多
Potassium ion batteries(PIBs)with high-volumetric energy densities are promising for next-generation low-cost energy storage devices.Metallic bismuth(Bi)with a structure similar to graphite,is a promising anode materi...Potassium ion batteries(PIBs)with high-volumetric energy densities are promising for next-generation low-cost energy storage devices.Metallic bismuth(Bi)with a structure similar to graphite,is a promising anode material for PIBs due to its high theoretical volumetric capacity(3763 mA h cm^−3)and relatively low working potential(−2.93 V vs.standard hydrogen electrode).However,it experiences severe capacity decay caused by a huge volume expansion of Bi when alloying with potassium.This study reports a flexible and free-standing Bi nanosheet(BiNS)/reduced graphene oxide composite membrane with designed porosity close to the expansion ratio of BiNS after charging.The controlled pore structure improves the electron and ion transport during cycling,and strengthens the structural stability of the electrode during potassiation and depotassiation,leading to excellent electrochemical performance for potassium-ion storage.In particular,it delivers a high reversible volumetric capacity of 451 mA h cm^−3 at the current density of 0.5 A g^−1,which is much higher than the previously reported commercial graphite material.展开更多
基金Natural Science Basic Research Plan in Shaanxi Province,Grant/Award Number:2024JC-YBMS-399The Key Research and Development Plan of Shaanxi Province,Grant/Award Number:2023-YBGY-168+1 种基金The Basic Research Program for Natural Science of Shaanxi Province,Grant/Award Number:2022JZ-50The Independent Research Project of the State Key Laboratory of Oral and Maxill of acial Reconstruction and Regeneration,Grant/Award Number:2021ZA05。
文摘Effectively controlling deep non-compressible bleeding remains a major challenge.In this study,by mimicking nanofiber structure and netting blood cells function of fibrin network in blood clots,we develop a novel bioinspired quaternized chitosan nanofiber sponge with distinct blood cells filtration and blood plasma absorption bifunction for rapid hemostasis.The quaternized chitosan nanofiber sponge possesses a unique gradient pore structure with small pores on the outer surface and large pores in the inner part.The outer small pores effectively capture blood cells with a filtration efficiency as high as 91.7%,while the inner large pores endow with an ultrahigh liquid absorption capacity(93 g/g),surpassing previously reported literature records.The quaternized chitosan nanofiber sponge demonstrates a hemostasis time 2.5 times faster than that of the commercial gelatin®hemostatic sponge when treating the rat liver defect bleeding(noncompressible hemorrhage model).When applied to the rabbit arterial injury bleeding(lethal arterial hemorrhage model),the bioinspired nanofiber sponge achieves bleeding control within only 61.6 s,while both commercial gelatin®hemostatic sponge and commercial collagen®hemostatic sponge fail to stop bleeding even after 240 s.This bioinspired nanofiber sponge derived from the physiological coagulation process may hold great potential for pre-hospital and battlefield first aid.
基金supported by the National Natural Science Foundation of China(grant Nos.U21A20321 and 21908138)Shanxi Province Central Government Guided Local Science and Technology Development Fund Project(grant No.YDZJSX2022A004)Shanxi Province Scientific and Technological Innovation Project of Colleges and Universities(grant No.2020L0009).
文摘Extraction of silica from fly ash to produce mesoporous silica materials is one of the most important utilization approaches.Mesoporous silica could not be synthesized on a large-scale by conventional sol-gel method.In this paper,facile preparation of mesoporous silica with controllable pore structure from fly ash by the template-free process via two steps of mineral phase transformation and selective acid etching was proposed.The influence of crystalline structure and acid etching degree on structure of as-synthesized mesoporous silica materials was revealed,as well as mechanism of crystalline structure transformation and pore structure formation.The results show that mullite and quartz could be transformed into acid-soluble kaliophilite when fly ash reacted with K_(2)CO_(3)at temperature of 800-1100℃.The hexagonal kaliophilite would be transformed into orthorhombic KAlSiO_(4)-O1 phase when the temperature is controlled at 1100℃.Mesoporous silica with specific surface area of 475.93 m^(2)/g and 642.57 m^(2)/g could be synthesized from activated fly ash with kaliophilite and KAlSiO_(4)-O1 phase crystalline structure.By controlling the degree of acid etching,mesoporous silica materials with different pore structures can be obtained.This paper provides a cost-effective and large-scale process for the preparation of mesoporous silica materials with controllable pore structure from solid waste fly ash.
基金This work was supported by the National Natural Science Foundation of China(51902176)China Postdoctoral Science Foundation(2018M631462)+1 种基金Guangdong Innovative and Entrepreneurial Research Team Program(2017ZT07C341)Shenzhen Municipal Development and Reform Commission and the Development and Reform Commission of Shenzhen Municipality for the development of the“Low-Dimensional Materials and Devices”Discipline.
文摘Potassium ion batteries(PIBs)with high-volumetric energy densities are promising for next-generation low-cost energy storage devices.Metallic bismuth(Bi)with a structure similar to graphite,is a promising anode material for PIBs due to its high theoretical volumetric capacity(3763 mA h cm^−3)and relatively low working potential(−2.93 V vs.standard hydrogen electrode).However,it experiences severe capacity decay caused by a huge volume expansion of Bi when alloying with potassium.This study reports a flexible and free-standing Bi nanosheet(BiNS)/reduced graphene oxide composite membrane with designed porosity close to the expansion ratio of BiNS after charging.The controlled pore structure improves the electron and ion transport during cycling,and strengthens the structural stability of the electrode during potassiation and depotassiation,leading to excellent electrochemical performance for potassium-ion storage.In particular,it delivers a high reversible volumetric capacity of 451 mA h cm^−3 at the current density of 0.5 A g^−1,which is much higher than the previously reported commercial graphite material.
