Subsurface irrigation by condensation of humid air

In this paper we report on the development tungsten oxide based chemiresistive sensors for the monitoring of oxygen at low temperatures (T ≤ 400 °C) in dry and humid air. The sensors were deposited onto alumina substrate by a combination of spin coating and a photolithographic process to define the sensing area. Our results show that the sensors comply with a linear relationship over a 0 to 20% concentration range, with a high response towards oxygen. The highest response was observed at 350 °C (ΔR/Ra = 7.8) in humid and in dry air (ΔR/Ra = 18). This result is a significant improvement over our previous experiments and we believe to take the concept of a metal-oxide based oxygen sensor a step closer.

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Numerical investigation on the thermal-flow performance of humid air-water in the interspace outside staggered tube bundles

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2020.120784 ◽

2021 ◽

Vol 166 ◽

pp. 120784

Author(s):

Hongqiang Ma ◽

Yemin Liu ◽

Caiqin Hou ◽

Gang Wang ◽

Xinmei Luo

Keyword(s):

Numerical Investigation ◽

Thermal Flow ◽

Humid Air ◽

Tube Bundles

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Growth of respiratory droplets in cold and humid air

Physical Review Fluids ◽

10.1103/physrevfluids.6.054303 ◽

2021 ◽

Vol 6 (5) ◽

Author(s):

Chong Shen Ng ◽

Kai Leong Chong ◽

Rui Yang ◽

Mogeng Li ◽

Roberto Verzicco ◽

...

Keyword(s):

Humid Air ◽

Respiratory Droplets

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Key Role of Transfer Layer in Load Dependence of Friction on Hydrogenated Diamond-Like Carbon Films in Humid Air and Vacuum

Materials ◽

10.3390/ma12091550 ◽

2019 ◽

Vol 12 (9) ◽

pp. 1550 ◽

Cited By ~ 6

Author(s):

Yunhai Liu ◽

Lei Chen ◽

Bin Zhang ◽

Zhongyue Cao ◽

Pengfei Shi ◽

...

Keyword(s):

Applied Load ◽

Carbon Films ◽

Diamond Like Carbon ◽

Low Friction ◽

Transfer Layer ◽

Humid Air ◽

Friction Mechanism ◽

Sharp Drop ◽

Practical Applications ◽

Load Dependence

The friction of hydrogenated diamond-like carbon (H-DLC) films was evaluated under the controlled environments of humid air and vacuum by varying the applied load. In humid air, there is a threshold applied load below which no obvious friction drop occurs and above which the friction decreases to a relatively low level following the running-in process. By contrast, superlubricity can be realized at low applied loads but easily fails at high applied loads under vacuum conditions. Further analysis indicates that the graphitization of the sliding H-DLC surface has a negligible contribution to the sharp drop of friction during the running-in process under both humid air and vacuum conditions. The low friction in humid air and the superlow friction in vacuum are mainly attributed to the formation and stability of the transfer layer on the counterface, which depend on the load and surrounding environment. These results can help us understand the low-friction mechanism of H-DLC film and define optimized working conditions in practical applications, in which the transfer layer can be maintained for a long time under low applied load conditions in vacuum, whereas a high load can benefit the formation of the transfer layer in humid air.

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