How to work 3,300 feet (1,000 metres) beneath the sea at normal atmospheric pressure

1978 ◽  
Vol 5 (2) ◽  
pp. 136
2013 ◽  
Vol 723 ◽  
pp. 157-162
Author(s):  
Jian Li ◽  
Qu Chao ◽  
He Ping

Under normal atmospheric pressure conditions, volume suddenly increases about 11% when the water freezes and decreased when the ice melts. The pressure can reach up to 2500 times of atmospheric pressure in the closed space when the water freezing. This is a very important characteristic of the natural world and the industrial. In low temperature condition, the snow on the pavement is easy to melt and freeze, and it will affect the road safety, increase the cracking of the road and accelerate asphalt pavement water damage. Bitumen is a mixture consisting of some extremely complex polymer hydrocarbons and hydrocarbon derivatives of non-metallic (oxygen, sulfur, nitrogen). Deicing salt is used to prevent freezing in that area, chloride salt is its main ingredient. When the water melting point reduced, it is not easy to icing but to penetrate the asphalt pavement. If the temperature is continued to reduce, salt solution will still freezing. At last, the pavement will form water damage in repeated freeze-thaw cycles conditions.


2018 ◽  
Vol 16 (36) ◽  
pp. 134-139
Author(s):  
Ahmed Mahmoud Shihab

In this research, non-thermal plasma system of argon gas is designed to work at normal atmospheric pressure and suitable for work in medical and biotechnological applications. This technique is applied in the treatment of the Staphylococcus epidermidis bacteria and show the role of the flow rate of Argon gas on the killing rate of bacteria, and it obtained a 100 % killing rate during the time of 5 minutes at the flow Argon gas of 5 liters/ min.


2010 ◽  
pp. 181-192
Author(s):  
Tetsuya Akitsu ◽  
Siti Khadijah Za aba ◽  
Hiroshi Ohkawa ◽  
Keiko Katayama-Hirayama ◽  
Masao Tsuji ◽  
...  

1957 ◽  
Vol 35 (5) ◽  
pp. 593-601
Author(s):  
James C. Hall ◽  
Helen I. Battle

Exposure of three species of frogs (Rana pipiens, R. clamitans, and R. sylvatica) to pressures of 1.5, 3.0, and 5.0 cm. Hg induces characteristic changes in the frequency and type of breathing. The immediate initial effect is that of increasing both mouth and lung oscillations for a brief period, prior to a gradual decline in rate. Lung oscillations persist longer than mouth oscillations, and on return to normal atmospheric pressure, are initiated earlier and at a rapid rate. During advanced stages of decompression, excess lung inflation is resultant from several consecutive inhalations, prior to a deep exhalation. R. pipiens is most resistant to low pressure, and R. sylvatica least resistant. Large individuals of a species survive longer than small. Survival is better with little oxygen in an atmosphere of nitrogen at normal atmospheric pressure than with a comparable oxygen supply at a reduced pressure. A brief acclimatization to pressures of 1.5 and 3.0 cm. Hg can be produced by prolonged exposure to 15 cm. Hg but not by intermittent exposures to low pressure.


Sign in / Sign up

Export Citation Format

Share Document