Effect on efficiency

Vi.scosity - Viscous liquids generally have a prejudicial effect on efficiency. As the viscosity of the fluid goes up, generally the effieiency of most pumps goes down. There are exceptions. 

The 50% reaction turbine has the highest efficiency of all the various types of turbines. Equation (9-15) shows the effect on efficiency is relatively small for a wide range of blade speed ratios (0.6-1.3). 

Determine effect on efficiency by Colburn s relation (see Efficiency section). 

Steam inlet pressure also has an effect on efficiency, although to a lesser extent. However, the cycle pressure is more often dictated by design limitations of the boiler for the application as well as the output. 

As a rough guide the upper limit of 1// can be taken as 0.1 below this figure the effect on efficiency will be small. The optimum design value may be above this figure, see Fair (1963). 

Mechanisms to encourage price competition in the pharmaceutical market and their effects on efficiency and welfare... 

It is important to note that, at least for neutral compounds, temperature has only a small effect on efficiency when the column is operated at its optimum flow velocity. Above the optimum velocity, temperature has a beneficial effect on efficiency, whereas below the optimum velocity, increased solute diffusion has a relatively large negative effect on efficiency [32,82,83]. 

Column packing structure, 125 Column packing, effect on efficiency, 11 ffii r ) wiijeulHit, II2 I) particle size distribution of, 6, 7 porosity of, 6 structure of, 11... 

Material Flow properties of composition Non-Segregation of ingredients of compn Pelletting Power Retardation of Rate of Burning Sparkiness of Flame Effect on Efficiency of Composition Ignitability of Composition Sensitiveness of Composition Waterproofing Power of Materials Remarks... 

It is important, first, to realize that efficiency is not a function solely of the column. Bad extracolumn parameters, such as detector cell volume or tubing diameters, can make the best column in the world look terrible. Second, efficiency measurements are very poor ways of comparing or purchasing columns unless all other parameters are constant. Many columns are bought and sold because they have a higher plate count than someone else s column. The efficiency calculations could have been made with different equations, on different compounds, on different machines, at different flow rates, all of which will have a profound effect on efficiency. The only valid use of plate counts that I have found is in column comparisons where all other variables are equal, or in following column aging over a period of days or months. 

The above conclusions are relevant in comparing gel electrophoresis and electrophoresis in free solution. The polymer strands of the gel network are necessary to produce a selective sieving effect, but they increase /. This, by itself, has no adverse effect on efficiency N, but by reducing mobility (Eq. 8.19), it reduces separation speed as expressed by Eq. 8.36. This loss of speed can be offset by increasing the temperature, thus decreasing the local viscosity of the solution between the polymer strands and correspondingly decreasing /. 

Using arc-shaped downcomers. Special tray designs (166,169) have arc-shaped downcomers, which direct liquid toward the column walls. These devices improve flow patterns, but their effect on efficiency has not been tested. 

Reflux ratio. Reflux ratio was stated to have a small effect on efficiency (5). 

Different type of system. Sections 7.3.1 and 7,3.4 suggest that if liquid viscosity, relative volatility, surface tension, and surface tension gradients are similar, one can expect similar efficiencies. Since it is difficult to attain similarity in all these, it is best to scale up from the same chemical system. Further, in aqueous-organic systems where surface tension gradients can be steep, concentration has a marked and unpredictable effect on efficiency (116,184,187). Data collected in one concentration range may scale up poorly to another. 

The pharmacist must also take an active role in the development, implementation, and review of an organization s policies, procedures, and protocols. The pharmacist should ensure that all aspects of care are addressed, including patient care, drug preparation and dispensing, quality control, infection control, and equipment maintenance. Involvement in such activities can have far-reaching effects on efficiency and financial outcomes. 

The reader should note the effect on efficiency of bus section failure and the location of the failure. 

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