Large Footprint

Chemical and hazardous materials industry infrastructure includes substantial facility and equipment investment it is highly capital intensive. Most chemical industry facilities contain very specialized process equipment that would be difficult to replace quickly. A good example is an oil refinery plant, where if the cracking facilities were destroyed they could not be replaced anytime soon. It is interesting to note that some chemical industry facilities (e.g., oil refineries) require large amounts of land (have a large footprint) but are typically staffed with few employees relative to on-site land requirements. 

Gamma-ray spectrometers use scintillator detectors. These spectrometers sense y-rays from all directions, and hence have large "footprints" (commonly hundreds of kilometers diameter) with sizes determined by orbital elevation above the surface. The y-rays come from depths of less than a meter in the target material. 

Tubular Plug resistant Easily (mechanically) cleaned Large footprint High capital cost... 

In summary, large footprint measurements permit an estimate of gas transfer velocities, but these estimates are sensitive to model assumptions. Furthermore, large footprint measurements give no direct information on the characteristics of surface renewal. Also, the method is extremely sensitive to drift in the calibration of either the surface or the bulk temperature measurement. 

Thus a very significant enhancement can be obtained. In addition and again because of the grazing incidence geometry, the incident beam can have a large footprint so that it samples a large number of scatterers. 

The footprint of an enzyme becomes an important issue if adsorption is limited by the outside area of the coated channels, since the area of the footprint is inversely proportional to the amount of protein adsorbed. The mobility or overall diffusivity of the protein is also important when working under inertial or electrical fields that affect the mobility. The length of the spacer arm is a well-known fundamental issue in protein adsorption, but it will become determinant when proteins of large footprint must be adsorbed in scarce sites. 

Disadvantages inelude the sometimes large footprint that results from having to provide up to three separate ehambers (wash, rinse, and steneil), and the sometimes inadequate agitation (spray pressure) generated by the maehine. This ean make it diffieult to elean fine-piteh apertures. 

Low surface area and packing density (especially tubular membranes) result in a large footprint. 

Low surface area and packing density (especially tubular membranes), large footprint and high power consumption - high cross-flow velocity required to prevent fouling results in increased head loss - makes cross-flow systems quite expensive (high Capex and Opex). They are, therefore, best suited for relatively small flows (up to 100 m /h) and special applications. Application of spiral-wound UF membranes is relatively new and limited to specific applications. 

The actuator materials currently used for MEMS have heen found to he suitable in all cases except one actuators for locomotion, gripping, and other interactions with the environment. Actuators made from inorganic materials face two key stumhhng blocks in this arena large footprints and brittleness. As pointed out in 1992 by Elwenspoek et al. [107], microrobots are still science fiction because there are no actuators usefiil for locomotion (and also no suitable miniature power supplies), and this situation has not changed in intervening years. 

Conventional actuators also suffer from relatively large footprint and this large size limits the degree of miniaturization and actuator densities that can be achieved. In contrast, arrays of polymer thermal actuators [108] have been fabricated that have a high actuator density and can be used to exploit parallel arrangements, such as for the handling of large objects. 

The challenge for the next generation of hydroelectric power professionals will be to modify this existing technology or explore the use of alternatives that do not require such a large footprint. Using water as it moves, without impeding its flow, is one possible way that hydroelectric power plants can better coexist with the populations they serve. 

Low-power and miniaturized electronic, electrical, infrared, and electro-optical sensors require miniaturized power sources or batteries to keep their size and weight to a minimum. The miniaturized power sources are nothing but three-dimensional (3D), thin-film microbatteries (MBs). Specific structural details of such a battery are illustrated in Figure 6.1. Deployment of conformal thin-film structures provides distinct advantages over conventional miniaturized structures. Additionally, the planar two-dimensional (2D) thin-film batteries cannot be classified as MBs, because they require large footprints of a few square centimeters to achieve a reasonable battery capacity. Studies performed by the author on miniaturized structures reveal that the maximum energy available from a thin-film battery is about 2 J/cm. Commercial thin-film batteries with a 3 cm footprint have a capacity of 0.4 mAh, which comes to about 0.133 mAh/cm. Thus, the 3D, thin-film, Li-ion, MB can meet the power requirements for low-power, miniaturized... 

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