Molybdenum-based materials have been intensively investigated for high-performance gas sensor applications.Particularly,molybdenum oxides and dichalcogenides nanostructures have been widely examined due to their tunab...Molybdenum-based materials have been intensively investigated for high-performance gas sensor applications.Particularly,molybdenum oxides and dichalcogenides nanostructures have been widely examined due to their tunable structural and physicochemical properties that meet sensor requirements.These materials have good durability,are naturally abundant,low cost,and have facile preparation,allowing scalable fabrication to fulfill the growing demand of susceptible sensor devices.Significant advances have been made in recent decades to design and fabricate various molybdenum oxides-and dichalcogenides-based sensing materials,though it is still challenging to achieve high performances.Therefore,many experimental and theoretical investigations have been devoted to exploring suitable approaches which can significantly enhance their gas sensing properties.This review comprehensively examines recent advanced strategies to improve the nanostructured molybdenum-based material performance for detecting harmful pollutants,dangerous gases,or even exhaled breath monitoring.The summary and future challenges to advance their gas sensing performances will also be presented.展开更多
Low-labor production of tissue-engineered muscles(TEMs)is one of the key technologies to realize the practical use of muscleactuated devices.This study developed and then demonstrated the daily maintenance-free cultur...Low-labor production of tissue-engineered muscles(TEMs)is one of the key technologies to realize the practical use of muscleactuated devices.This study developed and then demonstrated the daily maintenance-free culture system equipped with both electrical stimulation and medium replacement functions.To avoid ethical issues,immortal myoblast cells C2C12 were used.The system consisting of gel culture molds,a medium replacement unit,and an electrical stimulation unit could produce 12 TEMs at one time.The contractile forces of the TEMs were measured with a newly developed microforce measurement system.Even the TEMs cultured without electrical stimulation generated forces of almost 2mN and were shortened by 10%in tetanic contractions.Regarding the contractile forces,electrical stimulation by a single pulse at 1 Hz was most effective,and the contractile forces in tetanus were over 2.5 mN.On the other hand,continuous pulses decreased the contractile forces of TEMs.HE-stained cross-sections showed that myoblast cells proliferated and fused into myotubes mainly in the peripheral regions,and fewer cells existed in the internal region.This must be due to insufficient supplies of oxygen and nutrients inside the TEMs.By increasing the supplies,one TEM might be able to generate a force up to around 10 mN.The tetanic forces of the TEMs produced by the system were strong enough to actuate microstructures like previously reported crawling robots.This daily maintenance-free culture system which could stably produce TEMs strong enough to be utilized for microrobots should contribute to the advancement of biohybrid devices.展开更多
基金partly supported by the JSPS Grant-in-Aid for Scientific Research(No.JP16H06439,No.20H00297)by the Dynamic Alliance for Open Innovation Bridging Human,Environment and Materials in Network Joint Research Center for Materialsfinancial grants provided by Indonesia Ministry of Education,Culture,Research,and Technology,under the scheme of Basic Research Program No.2/E1/KP.PTNBH/2021 managed by Institut Teknologi Bandung。
文摘Molybdenum-based materials have been intensively investigated for high-performance gas sensor applications.Particularly,molybdenum oxides and dichalcogenides nanostructures have been widely examined due to their tunable structural and physicochemical properties that meet sensor requirements.These materials have good durability,are naturally abundant,low cost,and have facile preparation,allowing scalable fabrication to fulfill the growing demand of susceptible sensor devices.Significant advances have been made in recent decades to design and fabricate various molybdenum oxides-and dichalcogenides-based sensing materials,though it is still challenging to achieve high performances.Therefore,many experimental and theoretical investigations have been devoted to exploring suitable approaches which can significantly enhance their gas sensing properties.This review comprehensively examines recent advanced strategies to improve the nanostructured molybdenum-based material performance for detecting harmful pollutants,dangerous gases,or even exhaled breath monitoring.The summary and future challenges to advance their gas sensing performances will also be presented.
基金supported by JSPS KAKENHI Grant Number 16KK0147,JKA foundation(Japan Keirin Autorace).
文摘Low-labor production of tissue-engineered muscles(TEMs)is one of the key technologies to realize the practical use of muscleactuated devices.This study developed and then demonstrated the daily maintenance-free culture system equipped with both electrical stimulation and medium replacement functions.To avoid ethical issues,immortal myoblast cells C2C12 were used.The system consisting of gel culture molds,a medium replacement unit,and an electrical stimulation unit could produce 12 TEMs at one time.The contractile forces of the TEMs were measured with a newly developed microforce measurement system.Even the TEMs cultured without electrical stimulation generated forces of almost 2mN and were shortened by 10%in tetanic contractions.Regarding the contractile forces,electrical stimulation by a single pulse at 1 Hz was most effective,and the contractile forces in tetanus were over 2.5 mN.On the other hand,continuous pulses decreased the contractile forces of TEMs.HE-stained cross-sections showed that myoblast cells proliferated and fused into myotubes mainly in the peripheral regions,and fewer cells existed in the internal region.This must be due to insufficient supplies of oxygen and nutrients inside the TEMs.By increasing the supplies,one TEM might be able to generate a force up to around 10 mN.The tetanic forces of the TEMs produced by the system were strong enough to actuate microstructures like previously reported crawling robots.This daily maintenance-free culture system which could stably produce TEMs strong enough to be utilized for microrobots should contribute to the advancement of biohybrid devices.
