This novel face mask is designed to be a reusable respirator with a small and highly efficient disposable fabric filter.Respirator material requirements are reduced by 75%compared to traditional designs and allow repe...This novel face mask is designed to be a reusable respirator with a small and highly efficient disposable fabric filter.Respirator material requirements are reduced by 75%compared to traditional designs and allow repeated cleaning or sterilization.The probability of virus particle inhalation is reduced using novel air filtration pathways,through square-waveform design to increase filter airflow.Air enters the mask from right and left side filters,while the area in front of the mouth is isolated.Clear epoxy is used for a transparent frame,allowing lip-reading,and mask edges contain a silicone seal preventing bypass of the filters.The mask is manufactured using silicone molds,eliminating electricity requirements making it economical and viable in developing countries.Computational fluid dynamics numerical studies and Fluent ANSYS software were used to simulate airflow through the filter to optimize filter air path geometry and validate mask design with realistic human requirements.The breathing cycle was represented as a transient function,and N95 filter specifications were selected as a porous medium.The novel design achieved 1.2×10^(−3) kg s^(−1),20%higher than human requirements,with air streamlines velocity indicating local high speed,forcing and trapping virus particles against filter walls through centrifugal forces.展开更多
It is well known that small biomaterial particles can lead to superior properties demanded by advanced applications in tissue engineering. Electrospraying has been considered as a promising approach to prepare fine pa...It is well known that small biomaterial particles can lead to superior properties demanded by advanced applications in tissue engineering. Electrospraying has been considered as a promising approach to prepare fine particles, but reducing the particle size during such jetting process is always challenging. This is because the size of the as-sprayed particles is always limited by the device outlet diameter used. In the study we show that hydroxyapatite (HA) relics of 2 - 3 μm with low standard deviation can be deposited using a large nozzle (diameter of 1100 μm) only by reducing the nozzle tip angle from 90° to 15°. The mechanism of such phenomenon was extensively discussed, and a range of refined HA patterns were successfully prepared using the updated electrspraying configuration. We anticipate our findings to have a significant impact on the research of nanostructured biomaterials with superior properties which are realized by reducing the particle size using a greener electrically-driven processing technique.展开更多
文摘This novel face mask is designed to be a reusable respirator with a small and highly efficient disposable fabric filter.Respirator material requirements are reduced by 75%compared to traditional designs and allow repeated cleaning or sterilization.The probability of virus particle inhalation is reduced using novel air filtration pathways,through square-waveform design to increase filter airflow.Air enters the mask from right and left side filters,while the area in front of the mouth is isolated.Clear epoxy is used for a transparent frame,allowing lip-reading,and mask edges contain a silicone seal preventing bypass of the filters.The mask is manufactured using silicone molds,eliminating electricity requirements making it economical and viable in developing countries.Computational fluid dynamics numerical studies and Fluent ANSYS software were used to simulate airflow through the filter to optimize filter air path geometry and validate mask design with realistic human requirements.The breathing cycle was represented as a transient function,and N95 filter specifications were selected as a porous medium.The novel design achieved 1.2×10^(−3) kg s^(−1),20%higher than human requirements,with air streamlines velocity indicating local high speed,forcing and trapping virus particles against filter walls through centrifugal forces.
文摘It is well known that small biomaterial particles can lead to superior properties demanded by advanced applications in tissue engineering. Electrospraying has been considered as a promising approach to prepare fine particles, but reducing the particle size during such jetting process is always challenging. This is because the size of the as-sprayed particles is always limited by the device outlet diameter used. In the study we show that hydroxyapatite (HA) relics of 2 - 3 μm with low standard deviation can be deposited using a large nozzle (diameter of 1100 μm) only by reducing the nozzle tip angle from 90° to 15°. The mechanism of such phenomenon was extensively discussed, and a range of refined HA patterns were successfully prepared using the updated electrspraying configuration. We anticipate our findings to have a significant impact on the research of nanostructured biomaterials with superior properties which are realized by reducing the particle size using a greener electrically-driven processing technique.
