Emission Coefficient

Phase Emission coefficient Temperature, C Ref, Year Remarks 

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H. S. Eggleston, in Ammonia Emissions in Europe Emission Coefficients and Abatement Costs, Proceedings of a Workshop 4-6 February 1991, ed. G. Klaassen, IIASA, Laxenburg, Austria,... 

The three coefficients relating to x-rays in Equation 4-13 may conveniently be combined into a mass emission coefficient, k - If this is done, the equation becomes... 

In his treatment, Sherman makes use of emission coefficients t that perform the function of the empirical k in Equation 6-4. Both quantities are proportional to. the product of absorption coefficient, of fluorescence yield and of (1 — 1/r), where r is the absorption-jump ratio involved (4.4). 

Swamy M, Bhattacharya, S. Budgeting anthropogenic greenhouse gas emission from Indian livestock using country specific emission coefficients. Current Science. 2006 91 1340-53. 

For the case in which the electronic transition is much faster than vibrational relaxation, one has to use the single-vibronic level rate constant and in analyzing the transient absorption or stimulated emission spectra, the single-vibronic level absorption or stimulated emission coefficient should be used. For... 

The emission coefficient was taken to be a constant value close to unity. The configuration factor, F, was calculated in a conventional way, treating the center of each strip as a point. Once the downward flame spread started the radiation from the wall flames and the pyrolysing lining material behind the flames was added to the smoke layer radiation. The heat flux to the walls was then calculated from the expression... 

Let us consider a molecule and two of its energy levels E) and f 2- The Einstein coefficients are defined as follows (Scheme B2.2) Bn is the induced absorption coefficient, B2i is the induced emission coefficient and A21 is the spontaneous emission coefficient. 

Once electrons have been emitted by the photocathode, they are accelerated by an applied voltage induced between the photocathode and the first dynode (Uq in Figure 3.17). The dynodes are made of CsSb, which has a high coefficient for secondary electron emission. Thus, when an electron emitted by the photocathode reaches the first dynode, several electrons are emitted from it. The amplification factor is given by the coefficient of secondary emission, S. This coefficient is defined as the number of electrons emitted by the dynode per incident electron. Consequently, after passing the first dynode, the number of electrons is multiplied by a factor of 5 with respect to the number of electrons emitted by the photocathode. The electrons emitted by this first dynode are then accelerated to a second dynode, where a new multiplication process takes place, and so on. The gain of the photomultiplier, G, will depend on the number of dynodes, n, and on the secondary emission coefficient, 5, so that... 

Now calculate the minimum light power that can be measured with a photomultiplier using the photocathode of Exercise 3.5 and with 10 dynodes, each of which has a secondary emission coefficient of 5 = 6. Estimate these minimum powers if the photocathode is cooled down to 5 °C. Assume a bandpass width of 1 Hz. 

In recent years metliines, hemicyanines and cyanines have been the subject of much research as they couple high molar absorption and emission coefficients with a relative ease of molecular manipulation to change the wavelength of absorption, making them an obvious target for chemical designers. 

Fig. 9. Relative secondary-electron yield as a function of ion energy for Ne "—Na ", Ar —K ", and Kr —Rb. A constant quantity equal to the estimated potential-secondary-emission coefficient has been substracted from the raw noble gas data. (From Ref. )...

We will now use PSpice to find the diode current and voltage in the circuit of Figure 3-2. The diode current is given as Id= Is[exp(VD/riVT) - 1], Is is the diode saturation current and is 10 15 amps for this example. VT is the thermal voltage and is equal to 25.8 mV at room temperature, ri is the emission coefficient for the diode and its default value is 1. PSpice automatically runs all simulations at room temperature by default. 

Laser oscillation will start if N can be increased to a certain value Nc> called the critical inversion. Nc depends upon the spontaneous emission coefficient and the losses in the laser cavity. 

From the data of Hoogschagen and Gorter (104), the oscillator strength of the 5D4-+7F6 transition was obtained. By means of the Ladenburg formula, the spontaneous coefficient A46 was calculated. Using the relative-emission intensities, the rest of the A4J spontaneous-emission coefficients could be calculated. From these and a measured lifetime of 5.5 x 10 4 sec at 15°C, he calculated a quantum efficiency of 0.8 per cent. Kondrat eva concluded that the probability of radiationless transition for the trivalent terbium ion in aqueous solution is approximately two orders of magnitude greater than for the radiation transition. 

Specifically, the collision-induced absorption and emission coefficients for electric-dipole forbidden atomic transitions were calculated for weak radiation fields and photon energies Ha> near the atomic transition frequencies, utilizing the concepts and methods of the traditional theory of line shapes for dipole-allowed transitions. The example of the S-D transition induced by a spherically symmetric perturber (e.g., a rare gas atom) is treated in detail and compared with measurements. The case of the radiative collision, i.e., a collision in which both colliding atoms change their state, was also considered. 

Effects of Primary Beam Species Prediction of FABMS source sputtering yields can be generally supported by available data on secondary ion emission coefficients. For secondary ions detected at zero angle with respect to the surface normal, the secondary ion emission yield generally increases with the mass of the primary ions because of the... 

This expression disentangles the properties of the light polarization (coefficients /9, ( 1)), the geometry of two-electron emission (coefficients B t2(Ka, Kb)) and the dynamical parameters of the double photoionization process (coefficients A(ku k2, k)). The pkq(El) are the statistical tensors of the incident light which describe its polarization properties in the electric dipole approximation represented by 1. For linearly polarized light in which the electric field vector defines the z-axis of the coordinate frame, one has only two non-vanishing components given by (see equ. (8.99b))t... 

The insulation effect of the PTFE element is obvious if the temperature course is given as a function of the element position (see Figure 4.41). For this reason, the surface temperature of the six horizontal spacer bars was recorded. The surface temperatures of the spacer bars depend on the emissivity coefficient of the materials and on the surface characteristics. To eliminate these effects, the spacer bars were painted. 

According to Judd-Ofelt theory, one can evaluate the radiative lifetime of any excited state of interest via Einstein spontaneous emission coefficients. The rate of relaxation, A, from an initial state fJ) to final state if J ) through radiative processes is given by (Condon and... 

A MCP is used in the PIMMS as a secondary electron multiplier (see Sect. 3.7). The electron current measured after MCP compared to the initial ion current is amplified by a factor of 10-1,000. The secondary electron emission coefficient is an averaged number of secondary electrons emitted after each impact. This number depends on the initial energies of the electrons or ions and so on the voltage applied to the MCP. The amplification factor of a MCP configuration is expressed as ... 

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