Sharks are, by tradition, the eternal threat facing divers. Yet, a diver is quite a lot more unlikely to meet such a creature under the water than, at some time or another, to come up against an even greater danger – hypothermia, or exposure. To enable divers to prevent this syndrome from creeping silently up on them, two researchers from the Area of Applied Physics at the University Jaume I (Spain) have formulated an equation that enables divers to calculate the time they can safely remain submerged in the water at a certain temperature before the onset of exposure.
Taking into account parameters such as the initial body temperature, the rate at which body heat is produced, the temperature of the water and the thickness of the diving suit, among others, the formula provides an estimated value for the amount of time it will take the diver to reach a level of heat loss that is critical for his or her survival. If the mean temperature of the human body is 37 ºC, exposure comes about when the temperature drops below 35 ºC, and collapse and death can occur when it reaches 30 ºC.
“The exchange of energy between the diver and the water is less relevant when we are dealing with the physics of scuba diving because the limited supply of air in the bottles means that dives usually last less than an hour. It is, however, important in breath-hold or apnea diving, where divers are often underwater for over three hours,” explains Marcelo Aguilella Arzo, one of the authors, in a paper published in the American Journal of Physics.
Hugo Cerdà | alfa
Climate cycles may explain how running water carved Mars' surface features
02.12.2016 | Penn State
What do Netflix, Google and planetary systems have in common?
02.12.2016 | University of Toronto
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy