where is the difference in density of particles separated by a height difference of, is Boltzmann's constant ( namely, the ratio of the universal gas constant,, to Avogadro's number, ), and is the absolute temperature.

Short transitional periods, which are marked by some difference in humidity but by little change in temperature, intervene between the alternating seasons.

This difference stems from temperature dependency differences between the two reactions ; pp-chain reactions start occurring at temperatures around, making it the dominant energy source in smaller stars.

The operation of a heat engine is based on a difference in temperature that is converted to a mechanical output.

This heat loss through the glass keeps the internal bulb temperature steady so that the two sides of the vanes can develop a temperature difference.

High inside pressure inhibits motion because the temperature differences are not enough to push the vanes through the higher concentration of air: there is too much air resistance for " eddy currents " to occur, and any slight air movement caused by the temperature difference is damped by the higher pressure before the currents can " wrap around " to the other side.

Years after this explanation was dismissed, Albert Einstein showed that the two pressures do not cancel out exactly at the edges of the vanes because of the temperature difference there.

The only practical difference is that the two types have temperature coefficients of opposite polarities.

Similarly, thermocouples use the Peltier-Seebeck effect to measure the temperature difference between two points.

According to Carnot's principle, work can only be done when there is a temperature difference, and the work should be some function of the difference in temperature and the heat absorbed.

The exact choice of quiescent current, the standing current through both devices when there is no signal, makes a large difference to the level of distortion ( and to the risk of thermal runaway, that may damage the devices ); often the bias voltage applied to set this quiescent current has to be adjusted with the temperature of the output transistors ( for example in the circuit at the beginning of the article the diodes would be mounted physically close to the output transistors, and chosen to have a matched temperature coefficient ).

Jacob Bjerknes in 1969 contributed to an understanding of ENSO by suggesting that an anomalously warm spot in the eastern Pacific can weaken the east-west temperature difference, disrupting trade winds that push warm water to the west.

The Rankine temperature scale was created to use degree intervals the same size as those of the Fahrenheit scale, such that a temperature difference of one degree Rankine ( 1 R ) is equal to a difference of 1 ° F, except that absolute zero is 0 R – the same way that the Kelvin temperature scale matches the Celsius scale, except that absolute zero is 0 K. The Fahrenheit scale uses ( in the same manner as the later Celsius scale ) the symbol ° to denote a point on the temperature scale and the letter F to indicate the use of the Fahrenheit scale ( e. g. " Gallium melts at 85. 5763 ° F "), as well as to denote a difference between temperatures or an uncertainty in temperature ( e. g. " The output of the heat exchanger experiences an increase of 72 ° F " and " Our standard uncertainty is ± 5 ° F ").

* Historical estimates of past climate changes suggest that the recent changes in global surface temperature are unusual.

Extrapolation of the expansion of the Universe backwards in time using general relativity yields an infinite density and temperature at a finite time in the past.

Variations in CO < sub > 2 </ sub >, temperature and dust from the Vostok, Antarctica | Vostok ice core over the past 450, 000 years

In the past, when high pressure high temperature ( HPHT ) techniques were used to produce diamond, the diamonds were typically very small free standing diamonds of varying sizes.

As the temperature of the spring rises, it unwinds and opens the valve, allowing fluid past the valve which allows the fan to spin at about 60 % to 90 % of shaft speed.

Ice cores and sediment cores are used to for paleoclimate reconstructions, which tell geologists about past and present temperature, precipitation, and sea level across the globe.

Paraffin wax refers to a mixture of alkanes that falls within the 20 ≤ n ≤ 40 range ; they are found in the solid state at room temperature and begin to enter the liquid phase past approximately.

Other fixed points were used in the past are the body temperature ( of a healthy adult male ) which was originally used by Fahrenheit as his upper fixed point ( to be a number divisible by 12 ) and the lowest temperature given by a mixture of salt and ice, which was originally the definition of.

Northern hemisphere temperature reconstructions for the past 2, 000 years

" The IPCC Third Assessment Report from 2001 summarised research at that time, saying "… current evidence does not support globally synchronous periods of anomalous cold or warmth over this time frame, and the conventional terms of ' Little Ice Age ' and ' Medieval Warm Period ' appear to have limited utility in describing trends in hemispheric or global mean temperature changes in past centuries ".

At any given pressure and for any given composition of rock, a rise in temperature past the solidus will cause melting.

Franklin and Hadley confirmed evaporation of highly volatile liquids, such as alcohol and ether, could be used to drive down the temperature of an object past the freezing point of water.

Borehole temperature profiles, ice cores, floral and faunal records, glacial and periglacial processes, stable isotope and other sediment analyses, and sea level records serve to provide a climate record that spans the geologic past.

Most recent simulations show " plausible " agreement with the measured temperature anomalies over the past 150 years when forced by natural forcings alone, but better agreement is achieved when observed changes in greenhouse gases and aerosols are also included.

:* Chemical signatures, particularly Mg / Ca ratio of calcite in Foraminifera tests, can be used to reconstruct past temperature.

From this source, certain equipment can be used to derive the sea surface temperature and water salinity from the past few centuries.

* Heating a magnet past its Curie temperature ; the molecular motion destroys the alignment of the magnetic domains.

** Letuš-graphs, in the following order, of water level, flow and temperature data for the past 30 days ( taken in Letuš by ARSO )

** Medlog-graphs, in the following order, of water level and temperature data for the past 30 days ( taken in Medlog by ARSO )

** Laško-graphs, in the following order, of water level, flow and temperature data for the past 30 days ( taken in Laško by ARSO )

** Veliko Širje-graphs, in the following order, of water level, flow and temperature data for the past 30 days ( taken in Veliko Širje by ARSO )

Various geometries have been proposed for use as ion temperature probes, for example, two cylindrical tips that rotate past each other in a magnetized plasma.

A record cold temperature of 450 ± 80 pK in a Bose – Einstein condensate ( BEC ) of sodium atoms was achieved in 2003 by researchers at MIT.

In April 2012 a multinational team of researchers from the University of Southern California, Delft University of Technology, the Iowa State University of Science and Technology, and the University of California, Santa Barbara, constructed a two-qubit quantum computer on a crystal of diamond doped with some manner of impurity, that can easily be scaled up in size and functionality at room temperature.

In the Chesapeake Bay, researchers found large temperature excursions ( changes from the mean temperature of that time ) during the Medieval Warm Period ( about 950 – 1250 ) and the Little Ice Age ( about 1400 – 1700, with cold periods persisting into the early 20th century ), possibly related to changes in the strength of North Atlantic thermohaline circulation.

Biolipid transesterification has also been recently shown by Japanese researchers to be possible using a super-critical methanol methodology, whereby high temperature, high-pressure vessels are used to physically catalyze the Biolipid / methanol reaction into fatty-acid methyl esters.

More recently, researchers have proposed that they may have helped to control the body temperature of the animal, in a similar way to the sails of the large carnivorous Spinosaurus or of the pelycosaur Dimetrodon ( and the ears of modern elephants and jackrabbits ).

In January 2012, the researchers announced that water exits the vents at a temperature possibly exceeding, making them among the hottest known undersea vents.

These higher temperature trends have been attributed by some researchers to global warming.

In the field of climate science, researchers compile and compare statistics such as temperature or atmospheric concentrations of carbon dioxide.

The efficiency of present thermal diodes is about 18 % between the temperature range of 200-300 degree celsius. The researchers have found various ways of improving the efficiency

: The high optimum temperature for T. aquaticus allows researchers to study reactions under conditions for which other enzymes lose activity.

In a 2001 study, researchers found that " it is possible to vaporize medically active THC by heating marijuana to a temperature short of the point of combustion, thereby eliminating or substantially reducing harmful smoke toxins that are normally present in marijuana smoke.

When it was created by researchers Dr. Naveed Zaidi, at the University of Durham in 2004 it was the first magnetic polymer to function at room temperature.

The researchers found the rise in gas temperature begins at about 700 light years from the black hole, giving the location of the Bondi radius.

Seasonal movements tend to follow the 20 ° C isotherm and researchers have concluded water temperature was the most important factor influencing fish distribution.

The researchers also discovered that, independent of wood type, the concentration of carcinogenic PAHs were the lowest when the temperature used during the production of the liquid smoke was 530-559 ° C.

Thus, urea is typically utilized for gel preparation ; however, researchers need to be aware that the amount of urea used will have an impact on the overall temperature required to separate the DNA ( Biometra, 2000 ).

The temperature within nests that have been monitored by researchers remained a constant throughout the incubation period which ranges from 65 – 90 days.

As more researchers confirmed and replicated de Mairan's result that plant rhythms persisted in constant darkness it became clear that the rhythms continued even while controlling for other possible influences, such as temperature.

Although researchers have not standardized tactile map variables these nine are usually included depending on the substrate, vibration, flutter, pressure ’ temperature, size, shape, texture / grain, orientation and elevation.

In another method, fullerite is compressed to lower pressures ( 2 – 20 GPa ) and then heated to a temperature in the range 300 – 2500 K. Extreme hardness of what now appears likely to have been nanodiamonds was reported by researchers in the 1990s.