Relative optimum efficiency

The relatively low efficiency of solar cells exposed to white light can be circumvented by using LSC as beam splitters and couple them to photovoltaic cells with optimum sensitivities in different spectral ranges, and hence using the solar spectrum in a more efficient fashion. 

This finding is relatively sobering, but pressure capabilities of modern UHPLC instruments do allow the user a greater leeway in resolution due to the extra pressure capacity. It is obvious that the use of sub-2 pm materials will provide even higher potential for resolution increase. Several constructed scenarios are compared in the next section (listed in Table 2.2) to demonstrate how this may appear in practice, u always has to be increased by the same factor as dp decreases to maintain the optimum efficiency, which induces tremendous pressure increases. At constant column length the pressure increases with the third power of the... 

The time course of protein synthesis within each kind of vesicle was then simulated, as a function of vesicle size. Our study can predict translation yield in a population of small liposomes down to the attoliter (10 L) range. Our results show that the efficiency of protein synthesis peaks at approximately 3 10 L (840 nm diam.) with a Poisson distribution of solutes, while a relative optimum is found at around 10 L (275 nm diam.) for the power-law statistics. Figure2 shows the time course of GFP synthesis in a vesicle of 10 L volume the protein copies accumulate over time, until the depletion of inner reagents stops the generation of new copies. 

Process Requirements. Typical inside dry-bulb temperatures and relative humidities used for preparing, processing, and manufacturing various products, and for storing both raw and finished goods, are Hsted in Table 1. In some instances, the conditions have been compromised for the sake of worker comfort and do not represent the optimum for the product. In others, the conditions Hsted have no effect on the product or process other than to increase worker efficiency. 

The first stage assures high carbon conversion and optimum slag removal. The second stage reduces the raw product gas temperature to about 1000°C. This latter step helps to improve cold gas efficiency relative to other slurry fed processes and to lower waste heat recovery costs (15—18). 

Rufli s calculations (Fig. 7.7a, b), indicated that the optimum pressure ratio for a CCGT plant is relatively low compared with that of a simple gas turbine (CBT) plant. In both cases, the optimum pressure ratio increa.ses with maximum temperature. Davidson and Keeley [6] have given a comparative plot of the efficiencies of the two plants (Fig. 7.9), showing that the optimum pressure ratio for a CCGT plant is about the same as that giving maximum specific work for a CBT plant. 

The smallest size difference that can be resolved is related to the pore volume, the solute shape, and the efficiency of the column (see Fig. 2.6). However, this is at very low loadings. At higher loadings the sample volume will contribute to zone broadening and may, in some cases, be the dominating factor for resolution. Thus, for fractionation, an optimum exists with respect to column efficiency (represented by the flow rate as operational parameter) and sample volume for processing a particular volume of feed per unit time. As a rule of thumb this optimum can be found at a relative sample volume of 2-5% of the column volume (Hagel et al., 1989). 

The use of both sub- and supercritical fluids as eluents yields mobile phases with increased diffusivity and decreased viscosity relative to liquid eluents [23]. These properties enhance chromatographic efficiency and improve resolution. Higher efficiency in SFC shifts the optimum flowrate to higher values so that analysis time can be reduced without compromising resolution [12]. The low viscosity of the eluent also reduces the pressure-drop across the chromatographic column and facilitates the... 

The column used was 25 cm long, 4.6 mm in diameter, and packed with silica gel particle (diameter 5 pm) giving an maximum efficiency at the optimum velocity of 25,000 theoretical plates. The mobile phase consisted of 76% v/v n-hexane and 24% v/v 2-propyl alcohol at a flow-rate of 1.0 ml/min. The steroid hormones are mostly weakly polar and thus, on silica gel, will be separated primarily on a basis of polarity. The silica, however, was heavily deactivated by a relatively high concentration of the moderator 2-propyl alcohol and thus the interacting surface would be covered with isopropanol molecules. Whether the interaction is by sorption or displacement is difficult to predict. It is likely that the early peaks interacted by sorption and the late peaks by possibly by displacement. 

The displacing fluid may be steam, supercritical carbon dioxide, hydrocarbon miscible gases, nitrogen or solutions of surfactants or polymers instead of water. The VSE increases with lower mobility ratio values (253). A mobility ratio of 1.0 is considered optimum. The mobility of water is usually high relative to that of oil. Steam and oil-miscible gases such as supercritical carbon dioxide also exhibit even higher mobility ratios and consequent low volumetric sweep efficiencies. 

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