Relative conversion efficiency

Relative conversion efficiency (relative to NaI(Te)), i.e. net detector output using a bialkali photomultiplier tube (PMT). 

Caesium iodide can also be used without an activator but at the expense of a much reduced relative conversion efficiency - 4—6% compared to 45 % and 85 % for the doped materials. The emission maximum at 315 nm means that better output would be obtained when using quartz-windowed photomultipliers. 

If an intensifier, such as the 85 mm presented here, is now replacing the screen, a relative gain of the order of x50 is obtained which results in a conversion factor of 1 to 7.5 (1 incident X photon --> 7.5 electrons). This conversion efficiency not only resolves the quantum sink problem but also increases the light level significantly to compensate for the low gamma fluxes obtained from radioactive sources. 

Prices of spandex fibers are highly dependent on thread size selling price generally increases as fiber tex decreases. Factors that contribute to the relatively high cost of spandex fibers include (/) the relatively high cost of raw materials, (2) the small size of the spandex market compared to that of hard fibers which limits scale and thus efficiency of production units, and (J) the technical problems associated with stretch fibers that limit productivity rates and conversion efficiencies. 

The excellent photosensitivity and relatively high energy conversion efficiencies obtained from the bulk hetcrojunction materials arc promising. The monochromatic power efficiencies for conjugated polymer photovoltaic devices are around... 

Linearly polarized, near-diffraction-hmited, mode-locked 1319 and 1064 nm pulse trains are generated in separate dual-head, diode-pumped resonators. Each 2-rod resonator incorporates fiber-coupled diode lasers to end-pump the rods, and features intracavity birefringence compensation. The pulses are stabilized to a 1 GHz bandwidth. Timing jitter is actively controlled to < 150 ps. Models indicate that for the mode-locked pulses, relative timing jitter of 200 ps between the lasers causes <5% reduction in SFG conversion efficiency. 

As the pig grows, it deposits progressively more fat relative to lean tissue. Thus food conversion efficiency decreases from 2.4 at 45-50 kg liveweight, to 2.76 at 68-73 kg, to 3.45 at 95-100 kg. Food conversion efficiency is the amount of food required per kg of liveweight gain. 

At a very optimistic conversion efficiency of 10 % and a price for H2 of 15 per GJ only 10 worth of H2/m2/year would be obtained thus severely constraining construction and operational expenditures. Obviously, the situation worsens if conversion efficiencies are lower. In spite of the critical importance of this consideration, relatively few studies on photobiological hydrogen production report conversion efficiencies, and when these are reported they typically fall well below 1 % (i.e. < 1 HVmVyear). 

The overall process performance, as measured by photon efficiency (number of incident photon per molecule reacted, like the incident photon to current conversion efficiency, or IPCE, for PV cells), depends on the chain from the light absorption to acceptor/donor reduction/oxidation, and results from the relative kinetic of the recombination processes and interfacial electron transfer [23, 28]. Essentially, control over the rate of carrier crossing the interface, relative to the rates at which carriers recombine, is fundamental in obtaining the control over the efficiency of a photocatalyst. To suppress bulk- and surface-mediated recombination processes an efficient separation mechanism of the photogenerated carrier should be active. 

However, most of these routes are still economically unattractive and the possibility of creating an equivalent petrochemistry based on biomass, which depends on raising the conversion efficiency and establishing cascades in which the residues of one product serve as inputs for another, still suffers from the relatively unattractive products derived from hemicellulose and lignin. Therefore, to bring back biomass into the chemical business , the utilization of biomass must be enhanced by integrating it into biorefinery (Fig. 2). 

Compared vdth partial oxidation, steam reforming has received more attention due to its relatively higher conversion efficiency [155]. 

Since Gratzel et al. introduced the dye-sensitized solar cells (DSSG) in 1991 using Ti02 films as anode electrodes [262], these cells have become the focus of intense investigation. Its low cost and relatively high efficiencies for sunlight conversion... 

The yield determined in a certain type of experiment usually strongly depends on the assumptions made about the formation mechanism. In the older literature, the excited molecules were often assumed to be produced solely in neutral excitations [127,139-143] and energy-transfer experiments with Stern-Volmer-type extrapolation (linear concentration dependence) were used to derive G(5 i). For instance, by sensitization of benzene fiuorescence, Baxendale and Mayer established G(5 i) = 0.3 for cyclohexane [141]. Later Busi [140] corrected this value to G(5 i) = 0.51 on the basis that in the transfer, in addition to the fiuorescing benzene state S, the S2 and S3 states also form and the 82- 81 and 83 81 conversion efficiencies are smaller than 1. Johnson and Lipsky [144] reported an efficiency factor of 0.26 0.02 per encounter for sensitization of benzene fluorescence via energy transfer from cyclohexane. Using this efficiency factor the corrected yield is G(5 i) = 1.15. Based on energy-transfer measurements Beck and Thomas estimated G(5 i) = 1 for cyclohexane [145]. Relatively small G(5 i) values were determined in energy-transfer experiments for some other alkanes as well -hexane 1.4, -heptane 1.1 [140], cyclopentane 0.07 [142] and 0.12 [140], cyclooctane 0.07 [142] and 1.46 [140], methylcyclohexane 0.95, cifi-decalin 0.26 [140], and cis/trans-decalin mixture 0.15 [142]. 

On the other hand, the sensitizer (8), which carries no protons, shows a high open-circuit potential compared to complex 22, due to the relative negative shift of the conduction-band edge induced by the adsorption of the anionic complex, although, as a consequence the short-circuit photocurrent is lower. Thus, there should be an optimal degree of protonation of the sensitizer in order to obtain optimum short-circuit photocurrent and open-circuit potential, which determines tile power conversion efficiency of the cell. 

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