Total efficiency reduced

The reduced total efficiency E (Equation 7) is normally used for separators that operate with Rf > 0. This gives the separation efficiency of the particles that are separated in the concentrated stream only due to the separating power of the separator. Therefore, E does not consider the particles that reach the underflow due to drag. 

For separators which operate with Rf > 0, the grade efficiency curve does not start at G = 0% (Figure 11JB). This is because the separator operation always gives a minimum efficiency almost equal to the flow ratio Rf. The reduced grade efficiency G may be obtained in the same way as the reduced total efficiency E ... 

Equation (17), obtained from Equation (10), shows that it is possible to estimate the total efficiency of cell separation when the curves of grade efficiency and feed size distribution are known. Based on Equations (16) and (17), it is possible to obtain a similar result for the reduced total efficiency (Equation 18). 

Rejection efficiency Screen efficiency Total efficiency Reduced total efficiency... 

It is interesting to find that the often used clarification number is in fact equal to the reduced total efficiency E j because it can be shown from the... 

The solid-liquid separation in hydrocyclones is never complete, because there is always liquid discharging with the solids through the underflow. The term separation efficiency used for the hydrocyclone is usually defined for measuring the capability of the hydrocyclone of separating the solids from the feed into the underflow. There are a number of different terms for the separation efficiency used in the literature. They include total efficiency, reduced total efficiency, grade efficiency, reduced grade efficiency, and cut size. 

There are two problems associated with total efficiency. First, if a hydrocyclone delivers both liquid and solid to the underflow and nothing to the overflow, an ideal total efficiency of 1 will result. Second, without any separation, a hydrocyclone, by simply splitting the feed to an overflow and an underflow, will result in certain guaranteed total efficiency. In order to overcome these weaknesses, several alternative definitions of efficiency are used. One of the definitions is the reduced total efficiency E ... 

Similar to the reduced total efficiency, a reduced grade efficiency G (x) is introduced as... 

Particulate filtration removes suspended liquid or solid materials whose size, shape, and mass allow them to remain airborne at the air velocity conditions present. Filters are available in a range of efficiencies, with higher efficiency indicating removal of a greater proportion of particles and of smaller particles. Moving to medium efficiency pleated filters is advisable to improve lAQ and increase protection for equipment. However, the higher the efficiency of the filter, the more it will increase the pressure drop within the air distribution system and reduce total airflow (unless other adjustments are made to compensate). It is important to select an appropriate filter for the specific application and to make sure that the HVAC system will continue to perform as designed. Filters are rated by different standards which measure different aspects of performance. 

In dealing with environmental questions, economists emphasize efficiency, social welfare, and the need for cost accountability. A basic principle for efficiency is that all costs be borne by the entity who generates them in production or consumption. For example, production and consumption of diesel fuel will be socially inefficient if significant resulting costs are shifted to others who happen to be downwind or downstream from the refinery that makes the fuel or the truck that burns it. The benefits of making and using the fuel should exceed the cost— society at large—or else the process reduces total social welfare. 

Reduced total analysis time (greater efficiency)... 

Apart from recapture of the injected electrons by the oxidized dye, there are additional loss channels in dye-sensitized solar cells, which involve reduction of triiodide ions in the electrolyte, resulting in dark currents. The Ti02 layer is an interconnected network of nanoparticles with a porous structure. The functionalized dyes penetrate through the porous network and adsorb over Ti02 the surface. However, if the pore size is too small for the dye to penetrate, that part of the surface may still be exposed to the redox mediator whose size is smaller than the dye. Under these circumstances, the redox mediator can collect the injected electron from the Ti02 conduction band, resulting in a dark current (Equation (6)), which can be measured from intensity-modulated experiments and the dark current of the photovoltaic cell. Such dark currents reduce the maximum cell voltage obtainable, and thereby the total efficiency. 

In addition to acting on enzyme kinetics, Glc-6-P solubilizes hexokinase, thus reducing the efficiency of the enzyme when the reaction product accumulates. The total... 

Dissolved air flotation in combination with flocculation can reduce oil content in refinery wastewater to levels approaching oil solubility [40]. According to Katz [41], DAF plus chemical aids for flocculation can be expected to reduce BOD and COD by 30-50% and to reduce total oil to the range 5-25 mg/L. Table 17 shows some data for oil removal from refinery wastewater [27]. Removal efficiencies range from 70 to 90%. The accepted design overflow rates for DAF units are between 60 and 120 L/min per square meter (1.5-3.0 gpm/sq ft) [17]. 

The emission intensity of the 4F3/2- 4/n/2 transition (laser transition) does not change appreciably for a range of x from 0.02 to 0.5. This is probably due to a balancing of the total capture cross section for the pump light with the reducing quantum efficiency of AFV1 state. Figure 32 shows the variation of threshold with concentration. Data were collected at room temperature. Curve A is for an FT-524 flash lamp with a half-width of approximately 100 /xsec, whereas curve B is for an FT-91 flash lamp with a half-width of approximately 10 psec in a small ellipse. 

The relatively small amount of glycogen in skeletal muscle (about 1% of its total weight) limits the amount of glycolytic energy available during all-out exertion. Moreover, the accumulation of lactate and consequent decrease in pH in maximally active muscles reduces their efficiency. Skeletal muscle, however, contains another... 

In PEM fuel cells, uniformity of the current density across the entire active area is critical for optimizing the fuel cell performance. A non-uniform current density in the fuel cell can drastically affect different parameters of the fuel cell, such as reduced reactant and catalyst utilization along the active area, decrease in total efficiency and lifetime, and durability failure modes. Thus, determination of the current density distribution information is vital for designing PEM fuel cells that achieve higher performance and longer life.130 A number of methods for measuring current distribution in PEM fuel cells have been demonstrated the following sections discuss some of these methods in further detail. 

A noteworthy point is, however, that the heat for the reboiler is supplied at 377 K, which is often available as waste heat in a chemical plant. Waste heat is usually rejected (hence the term "waste"), so heat integration could improve the process efficiency and reduce total exergy losses for the entire chemical plant (see Figure 10.14). Now, what Figure 10.14 shows is that heat integration can sometimes reduce the exergy losses of a chemical plant as well as reduce... 

The rate of electron transport in dye-sensitized solar cells is a major element of the overall efficiency of the cells. The injected electrons into the conduction band, from optically excited dye, can traverse the Ti(>2 network and can be collected at the transparent conducting glass or can react either with oxidized dye molecule or with the oxidized redox couple (recombination). The reaction of injected electrons into the conduction band with the oxidized redox mediator gives undesirable dark currents, reducing significantly the charge-collection efficiency, and thereby decreasing the total efficiency of the cell (Fig. 7). 

In the field of chemical reaction engineering considerable efforts are devoted to tackling the problem of limited selectivities with which intermediates can be produced in coupled parallel-series reactions. Typical and important examples are partial oxidations where the formation of undesired side products or total oxidation products significantly reduces process efficiencies. Despite the progress achieved in the field of catalysis, many important industrial reactions still suffer from not satisfying conversion-selectivity relationships [52],... 

In metal working, surfactants are used to emulsify lubricants for metal processing. To consider the losses from inadequate processing and finishing of metals would reduce the efficiency of manufacturing and under today s expectations of total quality management, the result would be unacceptable and so costly that it would grind to a halt. The cost of the loss of protection and replacement would add an unacceptable burden which would cripple the world economy. 

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