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Energy conservation laws

Let us calculate the work R performed by external forces during the motion of an elastic medium. For an infinitesimal interval of time dt the elastic body particle is shifted by a vector [Pg.422]

The integration of relations (13.130) and (13.131) makes it clear that the work accomplished by the external surface and volume forces for the duration of an infinitesimal period of time dt may be calculated as follows  [Pg.422]

Now let us transform the surface integral in (13.133) into a volume integral, using the Gauss formula. According to equation (13.15), the normal stresses, P , can be expressed by the stress tensor as follows  [Pg.422]

Substituting expression (13.134) into the surface integral and applying the Gauss formula, we find  [Pg.422]

Taking into account the symmetry of the stress tensor and the expression (13.8) for the deformation tensor, we can write [Pg.423]


As required by the energy-conservation law reflected by the (5-function in (2.44), each intradoublet transition is accompanied by emission or absorption of a phonon with energy hAo. [Pg.22]

To see this quantitatively the first entropy is required. Let the energies of the respective reservoirs be ET . Imagine a fixed region of the subsystem adjacent to each boundary and denote the energy of these regions by Es . Now impose the energy conservation laws... [Pg.58]

Neglecting the thermal resistance of metallic tube wall, the energy conservation law... [Pg.137]

Steady-state process variables are related by mass and energy conservation laws. Although, for reasons of cost, convenience, or technical feasibility, not every variable is measured, some of them can be estimated using other measurements through balance calculations. Unmeasured variable estimation depends on the structure of the process flowsheet and on the instrument placement. Typically, there is an incomplete set of instruments thus, unmeasured variables are divided into determinable or estimable and indeterminable or inestimable. An unmeasured variable is determinable, or estimable, if its value can be calculated using measurements. Measurements are classified into redundant and nonredundant. A measurement is redundant if it remains determinable when the observation is deleted. [Pg.44]

Because of the energy conservation law, the RF field strength of the centre band is scaled down to give up its energy to the effective RF fields of the... [Pg.12]

This result is expected and in agreement with the energy conservation law in PIPs since under the above condition, the PIP reduces to a normal RF pulse with no phase increment. Consequently, the sideband excitations vanish and there is no scaling and UPS for the centre band. [Pg.14]

In order to observe the energy conservation law in PIPs, the scaling factors of any PIP are constrained by the equation of co = 1- Since limA o° = h the RF fields of the sidebands acquire energy at the expanse of a reduced field strength of the centre band. However, the centre band only gives up to 59.5% of its energy since a minimum of 40.5% (= limA jr A,q = (2/7r)2) of the energy remains. [Pg.63]

A periodic pulse also introduces multiple effective RF fields that are symmetric in amplitude and anti-symmetric in phase. For the centre band RF field, the phase is not shifted and the strength is equal to the average value of the periodic pulse. Similar to the case of the PIP, all the phases and scaling factors of the RF fields can be obtained analytically and to fulfill the energy conservation law in periodic pulses, the scaling factors obey the equation ofEr=-oo = (/l2nns//l2)-... [Pg.63]

Because of the large number of rotational levels in the upper and lower states, the overlap between the exciting laser line and the dopp-ler broadened absorption profile may be nonzero simultaneously for several transitions (u", / ) (v, f) with different vibrational quantum numbers v and rotational numbers J. This means, in other words, that the energy conservation law allows several upper levels to be populated by absorption of laser photons from different lower levels. [Pg.19]

The heat of reaction of a process is given by the difference in the heats of formation of the reactants and products. On going from a reactant temperature of Tg to a product temperature of Tj, the energy change due to a chemical reaction is represented by the energy conservation law according toh- l... [Pg.28]

Hilbert [54] first pointed out this remarkable absence of energy conservation laws from general relativity, not long after Einstein published his theory. [Pg.721]

No laws of physics or thermodynamics are violated in such open dissipative systems exhibiting increased COP and energy conservation laws are rigorously obeyed. Classical equilibrium thermodynamics does not apply and is permissibly violated. Instead, the thermodynamics of open systems far from thermodynamic equilibrium with their active environment—in this case the active environment-rigorously applies [2-4]. [Pg.742]

Indices 1 and 2 here characterize the electron to the left and to the right of the barrier, is the velocity of electron motion towards the barrier, 2 , and E2 are the energies of electrons relative to the position of the bottoms of the corresponding conduction bands, f ) = 1 4- exp[(2 — 2 Fi)/T] 1 is the probability that the state with the Ex energy is occupied, [1 - f2(F 2) is the probability that the state into which an electron tunnels in accordance with the energy conservation law is unoccupied, E[) is the probability of... [Pg.32]

The energy conservation law cannot be used to determine the selfsimilarity exponent conservation of energy is ensured by the departure of the actual solution from the self-similar one in a small (tending to zero as the process develops) part of the gas. [Pg.118]

One of the main tasks in Ref. 5 is to formulate one of the most important laws in physics, the energy conservation law, in a spacetime where v > c is possible, and to find the connection between two regions of the space, where different vacuum properties prevail. The other main task is to find the magnitudes, which will determine the vacuum properties of this new region of the spacetime. [Pg.657]

Here k0 is the wave vector of the incident particle, x(K) is its spin wave function, and k is its spin coordinate. The second term in (4.3) is a superposition of products of scattered waves and the wavefunctions of all the possible molecular states that obey the energy conservation law ... [Pg.285]

The equation for temperature can be obtained from the energy conservation law for the flow... [Pg.493]

The complex (RHe)+ may be produced in different states, so that the reaction, Eq. (5), corresponds to a multichannel process. From the energy conservation law for the channel 0-+nwe obtain the following expression for the kinetic energy of the [3 electron ... [Pg.291]


See other pages where Energy conservation laws is mentioned: [Pg.722]    [Pg.161]    [Pg.109]    [Pg.112]    [Pg.205]    [Pg.1]    [Pg.1]    [Pg.11]    [Pg.12]    [Pg.24]    [Pg.24]    [Pg.277]    [Pg.277]    [Pg.714]    [Pg.768]    [Pg.32]    [Pg.82]    [Pg.250]    [Pg.398]    [Pg.112]    [Pg.118]    [Pg.166]    [Pg.659]    [Pg.286]    [Pg.313]    [Pg.76]    [Pg.20]    [Pg.311]   
See also in sourсe #XX -- [ Pg.19 ]

See also in sourсe #XX -- [ Pg.189 ]




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