This study presents a comprehensive optimization and comparative analysis of thermoelectric(TE)infrared(IR)detec-tors using Bi_(2)Te_(3) and Si materials.Through theoretical modeling and numerical simulations,we explo...This study presents a comprehensive optimization and comparative analysis of thermoelectric(TE)infrared(IR)detec-tors using Bi_(2)Te_(3) and Si materials.Through theoretical modeling and numerical simulations,we explored the impact of TE mate-rial properties,device structure,and operating conditions on responsivity,detectivity,noise equivalent temperature difference(NETD),and noise equivalent power(NEP).Our study offers an optimally designed IR detector with responsivity and detectivity approaching 2×10^(5) V/W and 6×10^(9) cm∙Hz^(1/2)/W,respectively.This enhancement is attributed to unique design features,includ-ing raised thermal collectors and long suspended thin thermoelectric wire sensing elements embedded in low thermal conductivity organic materials like parylene.Moreover,we demonstrate the compatibility of Bi_(2)Te_(3)-based detector fabrication pro-cesses with existing MEMS foundry processes,facilitating scalability and manufacturability.Importantly,for TE IR detectors,zT/κemerges as a critical parameter contrary to conventional TE material selection based solely on zT(where zT is the thermoelec-tric figure of merit andκis the thermal conductivity).展开更多
Cartilage and facial muscle tissue provide basic yet vital functions for homeostasis throughout the body, making human survival and function highly dependent upon these somatic components. When cartilage and facial mu...Cartilage and facial muscle tissue provide basic yet vital functions for homeostasis throughout the body, making human survival and function highly dependent upon these somatic components. When cartilage and facial muscle tissues are harmed or completely destroyed due to disease, trauma, or any other degenerative process, homeostasis and basic body functions consequently become negatively affected. Although most cartilage and cells can regenerate themselves after any form of the aforementioned degenerative disease or trauma, the highly specific characteristics of facial muscles and the specific structures of the cells and tissues required for the proper function cannot be exactly replicated by the body itself. Thus, some form of cartilage and bone tissue engineering is necessary for proper regeneration and function. The use of progenitor cells for this purpose would be very beneficial due to their highly adaptable capabilities, as well as their ability to utilize a high diffusion rate, making them ideal for the specific nature and functions of cartilage and facial muscle tissue. Going along with this, once the progenitor cells are obtained, applying them to a scaffold within the oral cavity in the affected location allows them to adapt to the environment and create cartilage or facial muscle tissue that is specific to the form and function of the area. The principal function of the cartilage and tissue is vascularization, which requires a specific form that allows them to aid the proper flow of bodily functions related to the oral cavity such as oxygen flow and removal of waste. Facial muscle is also very thin, making its reproduction much more possible. Taking all these into consideration, this review aims to highlight and expand upon the primary benefits of the cartilage and facial muscle tissue engineering and regeneration, focusing on how these processes are performed outside of and within the body.展开更多
Harvesting body heat using thermoelectricity provides a promising path to realizing self-powered,wearable electronics that can achieve continuous,long-term,uninterrupted health monitoring.This paper reports a flexible...Harvesting body heat using thermoelectricity provides a promising path to realizing self-powered,wearable electronics that can achieve continuous,long-term,uninterrupted health monitoring.This paper reports a flexible thermoelectric generator(TEG)that provides efficient conversion of body heat to electrical energy.The device relies on a low thermal conductivity aerogel–silicone composite that secures and thermally isolates the individual semiconductor elements that are connected in series using stretchable eutectic gallium-indium(EGaIn)liquid metal interconnects.The composite consists of aerogel particulates mixed into polydimethylsiloxane(PDMS)providing as much as 50%reduction in the thermal conductivity of the silicone elastomer.Worn on the wrist,the flexible TEGs present output power density figures approaching 35μWcm^(−2)at an air velocity of 1.2 ms^(−1),equivalent to walking speed.The results suggest that these flexible TEGs can serve as the main energy source for low-power wearable electronics.展开更多
基金supported by the National Science Foundation (NSF)under grant number CBET-2110603.
文摘This study presents a comprehensive optimization and comparative analysis of thermoelectric(TE)infrared(IR)detec-tors using Bi_(2)Te_(3) and Si materials.Through theoretical modeling and numerical simulations,we explored the impact of TE mate-rial properties,device structure,and operating conditions on responsivity,detectivity,noise equivalent temperature difference(NETD),and noise equivalent power(NEP).Our study offers an optimally designed IR detector with responsivity and detectivity approaching 2×10^(5) V/W and 6×10^(9) cm∙Hz^(1/2)/W,respectively.This enhancement is attributed to unique design features,includ-ing raised thermal collectors and long suspended thin thermoelectric wire sensing elements embedded in low thermal conductivity organic materials like parylene.Moreover,we demonstrate the compatibility of Bi_(2)Te_(3)-based detector fabrication pro-cesses with existing MEMS foundry processes,facilitating scalability and manufacturability.Importantly,for TE IR detectors,zT/κemerges as a critical parameter contrary to conventional TE material selection based solely on zT(where zT is the thermoelec-tric figure of merit andκis the thermal conductivity).
基金Acknowledgements The authors would like to thank the financial supports from Delta Dental, Osteo Science Foundation （Peter Geistlich Award）, Marquette Innovation Fund, AFOSR （FA9550-12-1-0225） and NSF （EEC-1160483, ECCS-1351533 and CMMI-1363485）.
文摘Cartilage and facial muscle tissue provide basic yet vital functions for homeostasis throughout the body, making human survival and function highly dependent upon these somatic components. When cartilage and facial muscle tissues are harmed or completely destroyed due to disease, trauma, or any other degenerative process, homeostasis and basic body functions consequently become negatively affected. Although most cartilage and cells can regenerate themselves after any form of the aforementioned degenerative disease or trauma, the highly specific characteristics of facial muscles and the specific structures of the cells and tissues required for the proper function cannot be exactly replicated by the body itself. Thus, some form of cartilage and bone tissue engineering is necessary for proper regeneration and function. The use of progenitor cells for this purpose would be very beneficial due to their highly adaptable capabilities, as well as their ability to utilize a high diffusion rate, making them ideal for the specific nature and functions of cartilage and facial muscle tissue. Going along with this, once the progenitor cells are obtained, applying them to a scaffold within the oral cavity in the affected location allows them to adapt to the environment and create cartilage or facial muscle tissue that is specific to the form and function of the area. The principal function of the cartilage and tissue is vascularization, which requires a specific form that allows them to aid the proper flow of bodily functions related to the oral cavity such as oxygen flow and removal of waste. Facial muscle is also very thin, making its reproduction much more possible. Taking all these into consideration, this review aims to highlight and expand upon the primary benefits of the cartilage and facial muscle tissue engineering and regeneration, focusing on how these processes are performed outside of and within the body.
基金supported by the Advanced Self-Powered Systems of Integrated Sensors and Technologies(ASSIST)a Nano-Systems Engineering Research Center funded by National Science Foundation(EEC1160483).
文摘Harvesting body heat using thermoelectricity provides a promising path to realizing self-powered,wearable electronics that can achieve continuous,long-term,uninterrupted health monitoring.This paper reports a flexible thermoelectric generator(TEG)that provides efficient conversion of body heat to electrical energy.The device relies on a low thermal conductivity aerogel–silicone composite that secures and thermally isolates the individual semiconductor elements that are connected in series using stretchable eutectic gallium-indium(EGaIn)liquid metal interconnects.The composite consists of aerogel particulates mixed into polydimethylsiloxane(PDMS)providing as much as 50%reduction in the thermal conductivity of the silicone elastomer.Worn on the wrist,the flexible TEGs present output power density figures approaching 35μWcm^(−2)at an air velocity of 1.2 ms^(−1),equivalent to walking speed.The results suggest that these flexible TEGs can serve as the main energy source for low-power wearable electronics.
