Introduction
The thermodynamic temperature standard is from William Thomson, the first generation Kairen Baron in 1848, the introduction of the second law of thermodynamics of. It is a pure theoretical temperature standard because it is independent of the attributes of the temperature measurement. Symbol T, unit K (Kairen, referred to as opening). One of the 7 basic amounts of the International Unit System (Si), the scales of thermodynamic temperature standard, symbols T. Depending on the principle of thermodynamics, the thermodynamic temperature is measured, and the international utility temperature standard is used. Thermodynamic temperature is an absolute temperature (Absolute Temperature). The unit is "Kairen", English is "Kelvin" is "Open", the international code "K", but does not add "°" to indicate the temperature. Kaewe Wen is named to commemorate the British physicist Lord Kelvin. With the absolute zero degrees (0k), the temperature of the three-phase point of the water is 273.16k, and the temperature of the thermodynamic temperature of the water three phase is defined is defined as 1/273.16 of the thermodynamic temperature of the water three phase.
degrees Celsius is a special name that is replaced by the Celsius Temperature Time. The three-phase point temperature of water is 0.01 degrees Celsius. Therefore, the relationship between the thermodynamic temperature T and the people's whateocker temperature T is: t (k) = 273.15 + t (° C). The unit opening (k) of the thermodynamic temperature is identical to the average value of the unit degrees Celsius (° C) of the Celsius. So
November 16, 2018, the International Metering Conference passed the resolution, 1 Kairwen is defined as "corresponding Bolzman constant is 1.380649 × 10-23J · K-1
(1.380649 Thermodynamic temperature when × 10-23kg · m2 · s-2 · k-1).
Thermodynamics and Celsius transmissions
expression is: t = t + 273.15 ° C
T is thermodynamic temperature standard T is Celsius temperature standard
It is the result of:
a certain mass gas in the case of constant temperature, the temperature per liter (or decreased) 1 ° C increases (or decrease) the pressure value equal to it at 0 ° C The pressure of 1/273 is expressed as the formula as
p = p0 (1 + t / 273)
where the pressure of the gas at the gas at 0 ° C
later Kelvin introduced the concept of "absolute zero", the temperature reached 0K, namely -273 ° C, stopped all exercise
later it was promoted to T = T + 273.15 ° C
essential
The temperature in the classic thermodynamics has no concept of extreme high temperature, only the theoretical minimum temperature "absolute zero". The third law of thermodynamics pointed out that "absolute zero" is unable to achieve limited steps. In statistical thermodynamics, the temperature is given a new physical concept - describes the thermodynamic amount of strength properties that can comproach (ie, entropy) in the system. This created the new theory field of "thermodynamic temperature range". Usually the system of environment and research in our survival is a system with unlimited quantum state. In such systems, the internal energy is always increased with the increase of the decreasing, and thus does not have a negative thermodynamic temperature. And a few have a limited amount of system, such as laser generating crystals, when continuous improvement of the internal energy of the system, it has reached an infinite temperature when the system chaos has changed, and it has reached an infinite temperature, and then further improves the internal energy of the system. That is, in a state where the so-called "particle luxing reversal" is reached, the internal energy is increased with the reduction in the decrease, and thus the thermodynamic temperature at this time is negative! However, there is no classic algebraic relationship between the negative temperature and the positive temperature here, and the negative temperature is more than a temperature higher than the positive temperature! The temperature standard concept of quantum statistical mechanics is: unlimited quantum state system: The lower limit and upper limit of the thermodynamic temperature of the absolute zero-grade system system is not achieved by the limited step.
The origin of
Kairen is the thermodynamic temperature unit named by the British scientist Kairen last name. In 1848, the British scientist William Tomson first proposed the theory of thermodynamics and quickly received international recognition. In 1854, William Tomson proposed that as long as a fixed point is selected, the unit of thermodynamics can be determined.
As early as 1787, the French physiologist, Charlie (J.CHARLES) found that when the pressure is constant, the temperature per liter is 1 ° C, the volume of the volume of the gas (expansion ratio) is one Set value, volume expansion and temperature is linear. The initial experiments derived the volume of the volume of the gas at 0 ° C, and later, many people have been revised for decades, especially in the 1802 French Galasac (Jlgay-Lussac) The work is finally determined 1/273.15. The relationship between the above gas volume and the temperature is represented by formula, as follows:
v = V 0 (1 + T / 273.15) = V 0 (T + 273.15) / 273.15
V is a gas volume at a temperature of T / ° C. If the T + 273.15≡t (which is 0 ° C + 273.15 = T0), the above relationship can be expressed in a simple formula: V / T = V 0 / t 0 0 < / sub>, further see, V 1 / t 1 = v 0 / t 0 , V 0 , V 0 > 2 / t 2 = v 0 / t 0 , naturally there is V 1 / t 1 = V 2 / t 2 , that is, a certain amount of gas at any temperature, when the pressure is constant, the volume V and use T is proportional to the temperature indicated by the temperature label. This is called Charlie - Cover Lesak. In fact, this relationship is only suitable for ideal gases. To this end, people first call T as the ideal gas temperature (temperature standard), but also known absolute temperature (temperature standard). After thermodynamic formation, it was found that the temperature label had a more profound physical meaning, especially Claosius and Kelvin demonstrated the absolute zero to reach, nucked that the thermodynamics temperature (temperature standard), and used Kelvin's first letter K is its unit. The temperature of the object is a macroscopic manifestation of a large amount of particulate motion (thermal movement) constituting the object.
Measurement method
Currently, the main thermodynamic temperature measurement method is: a calorific gas temperature gauge, gas acoustic temperature gauge, radiation thermometer method (including spectral bless thermometer and full bless Temperature meter), dielectric constant temperature gauge, noise temperature gauge, etc., the thermodynamic temperature measurement method of different principles is limited by its own conditions, suitable for different temperature ranges, mainly inducturing the temperature of the gas refractive index reference thermometer temperature measurement temperature .
Method of negative thermodynamics
From thermodynamic basic relationship ((e) s / (e) u) v = 1 / t and boltzmann distributed N2 / N1 = Exp (-ε / KT) Describes the thermodynamic temperature not only there is a positive value, but also the necessary conditions for negative temperatures in the nuclear spin balance system: must be a thermal balance system with an upper limit of energy (or level). Separants with the environment, and also need to be used for a certain external force.