Direct energy

Indirect Energy path Direct Energy path... 

The number of translational states per unit volume dR with directed energies E = (E, p) in the range [E, E +... 

Current is tire number of particles crossing unit area in unit time. The current in a beam with directed energy E within the range (E, E + d ) is... 

Now let us consider tire implications of tliese results for energy transfer. First we recognize tliat tliere is no directed energy transfer of tire fonn considered in the incoherent case. Molecules in tire dimer cannot be recognized as well defined separate entities tliat can capture and translate excitation from one to anotlier. The captured excitation belongs to tire dimer, in otlier words, it is shared by botli molecules. The only counteriDart to energy migration... 

The upper VB for ratile is composed of the 02p orbitals and is 5.52 eV wide. The lower 02s band has a width of 2.08 eV. These numbers agree well with the experimental values of 5.4 and 1.9 eV, respectively. 1 The calculated direct energy gap of 1.83 eV is in good agreement with other LDA results and is smaller than the experimental value of 3.0 eV. 1... 

Direct Energy Minimization Versus the Finite Element Methods. 144... 

As the pressure increases from low values, the pressure-dependent term in the denominator of Eq. (101) becomes significant, and the heat transfer is reduced from what is predicted from the free molecular flow heat transfer equation. Physically, this reduction in heat flow is a result of gas-gas collisions interfering with direct energy transfer between the gas molecules and the surfaces. If we use the heat conductivity parameters for water vapor and assume that the energy accommodation coefficient is unity, (aA0/X)dP — 150 I d cm- Thus, at a typical pressure for freeze drying of 0.1 torr, this term is unity at d 0.7 mm. Thus, gas-gas collisions reduce free molecular flow heat transfer by at least a factor of 2 for surfaces separated by less than 1 mm. Most heat transfer processes in freeze drying involve separation distances of at least a few tenths of a millimeter, so transition flow heat transfer is the most important mode of heat transfer through the gas. 

Remember that it is not the direct energy resonance between the vibrational levels in the two modes that is important. For cluster bond excitation, it is a resonance between the energy of the unoccupied vibrational levels in the weak cluster bond relative to the occupied excited level and quanta of thermal vibrational energy in... 

Such a process can naturally be expected to play a certain part in the mechanism of directed energy transport in biological systems, in particular, in the transfer of absorbed energy from the antenna chlorophyll molecules to the reactive center in the photosynthetic system of plants. In Ref. [30], energy exchange between molecules of the photosynthetic pigments chlorophyll a and pheophytin a was studied experimentally with pigments introduced into the polar matrix. 

Zenkevich RAN, El NNA, Tomin VI (1982) Directed energy transfer due to orientational broadening of energy levels in photosynthetic pigments solutions. J Lumin 26 367-376... 

Nemkovich NA, Rubinov AN, Tomin VI (1980) Directed energy transfer in rigid single component solutions. JTP Lett 6 270-273... 

Fernando, S. Adhikari, S. Chandrapal, C., et al., Biorefineries Current Status, Challenges, and Future Direction. Energy Fuels, 2006. 20 pp. 1727-1737. 

Rips and Silbey (1991) have reexamined the thermalization of photoelectrons (of a few eV in energy) with a master equation approach for the time rate of energy loss. Their method is quite general, and it includes both direct (energy loss) and inverse (energy gain) collisions according to the principle of detailed balance. As in the Frohlich-Platzman method, they first calculate the time rate... 

Thin-film solar cell devices based on CIGS have already demonstrated an efficiency of 19.52%.40 The direct energy gap of CIGS results in a large optical absorption coefficient, which, in turn, permits the use of thin (-1 pm) layers of active material. CIGS solar cells are also known for their long-term stability.76... 

In this scheme, M <1 and K equilibrium constants. Direct binding experiments have confirmed the generality of this scheme for nicotinic receptors. Thus, distinct conformational states govern the different temporal responses that ensue upon addition of a ligand to the nicotinic receptor. No direct energy input or covalent modification of the receptor channel is required. 

The utilization principles are shown in Figure 6, where the typical examples are enumerated. Hydrogen turbine has been studied by Japanese WE-NET project and the achieved energy efficiency was as high as about 60 %, which can be competitive with fuel cell system. One of the typical direct energy conversion systems, which have no movable parts and no noise, is fuel cell. Today topics of clean cars have been focused to the cars with PEMFC as was mentioned previously. 

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