Extended surface area

Stokes Vacuum, Inc. Price includes dryer, 15-lVin jacket, drive with motor, internal filter, and trunnion supports for concrete or steel foundations. Horsepower is established on 65 percent volume loading of material with a hulk density of 50 Ih/ft. Models of 250 ft, 325 ft, and 400 ft have extended surface area. 

The total surfece area, A, in the annulus is the sum of the extended surface area and the hare pipe surfeces not covered hy fins. See Table 10-40. The fm efficiency, rj, Cf or E, from Figure 10-154 is corrected for the percent surlace that is finned. The corrected value, is the effective surfece efficiency. 

Commercially available monolithic columns are based either on silica or organic polymer and are generally characterized as a polymeric skeleton with macropores, with a diameter of approximately 2 pm, and mesopores, with a diameter of approximately 13 nm. The role of the macropores (through-pores) is to provide channels with high compounds permeability, which permits the use of higher flow rates with respect to columns based on conventional particle size, and an extended surface area, which is comparable to conventional columns packed with 3 pm particles. 

Pt is, of course, not a good electrocatalyst for the O2 evolution reaction, although it is the best for the O2 reduction reaction. However, also with especially active oxides of extended surface area, the theoretical value of E° has never been observed. For this reason, the search for new or optimized materials is a scientific challenge but also an industrial need. A theoretical approach to O2 electrocatalysis can only be more empirical than in the case of hydrogen in view of the complexity of the mechanisms. However, a chemical concept that can be derived from scrutiny of the mechanisms mentioned above is that oxygen evolution on an oxide can be schematized as follows [59] ... 

The heat-transfer coefficient of an air cooler (Btu, per hour, per square foot of finned area, per degree Fahrenheit), is not particularly good. It might be 3 to 4, for cooling a viscous liquid, or 10 to 12 for condensing a clean vapor. The low heat-transfer coefficients are off-set by the large extended surface area. 

Oxide electrodes have been observed to be almost immune from poisoning effects due to traces of metallic impurities in solution [99]. This is undoubtedly due primarily to the extended surface area. It can be anticipated that the calcination temperature must have a sizable effect. But in addition, a different mechanism of electrodeposition must be operative. Chemisorption on wet oxides is usually weak because metal cations are covered by OH groups [479]. As a consequence, underpotential deposition of metals is not observed on Ru02, although metal electrodeposition does takes place. However, electrodeposited metals give rise to clusters or islands and not to a monomolecular layer like on Pt. Therefore, the oxide active surface remains largely uncovered even if metallic impurities are deposited [168]. Thus, the weak tendency of oxides to adsorb ions, and its dependence on the pH of the solution is linked to their favorable behavior observed as cathodes in the presence of metallic impurities. 

Step 4. Calculate the required tube outside extended surface area, Ax, with Eq. (5.24) ... 

Step 12. The air-side heat-transfer film coefficient HA (Btu/h °F ft2) is now calculated, using the GA value from step 11. Equation (5.43) is a data-fitted equation of several actual HA values vs. GA values. Note that the following HA calculated value is the tube extended surface area outside heat-transfer film coefficient. Equation (5.43) also is in good agreement with the GPSA Engineering Data Book [15], Sec. 10, Fig. 10-17. 

Primarily.- Energy transfer from heat under the material in the rotary kiln. The material, which is ground down to have extended surface area, is permanently mixed, which mixing process is promoted by the blades inside the reactor body. The heated material is to be permanently replaced by cooler materials again and again. Therefore the thermal conductivity of the biomass material is of less importance and can be within a wider range. This is a very important and vital technical factor, particularly in relation to the biomass refuses, which are usually bad thermal conductors and in practice are of mixed physical and chemical character. 

Extended Surface Area Roller Bottle (ESRB) (Bibby Sterilin Ltd). This polystyrene bottle has a ribbed or corrugated surface, doubling the surface area of the SSO-cm flask to 1700 cm. ... 

Roll Mills Roll mills can provide extremely high localized shear while retaining extended surface area for temperature control. A typical roll mill has two parallel rolls mounted in a heavy frame with provisions for accurately regulating the pressure and distance between the rolls. Since one pass between the rolls does only a little blending, the mills are usually used as a series of mixers. Only a small amount of material is in the high-shear zone at a time, thus allowing time and exposure for cooling. 

In the transport industry, the most important application is the de-icing and de-misting of large extended surface areas by transparent and electrically conductive coatings and there are, in addition, some solar control applications. 

The A. coerulea material was poorly crystalline, showing a broad peak at 20° 20, but the spectrum for the alkali-treated material showed a broad peak at 10.72° and two peaks at 18.72° and 19.98° 20, with close similarity to the spectrum of authentic chitosan. Optical microscopy showed that the alkali-treated products, stained with Saphranine or with other stains, preserved the morphology of the fungus, with flattened and empty structures [30] (Fig. 1). This work introduced the concept that an extended surface area of the carbohydrate polymer leads to enhanced performance, as amply confirmed by most recent works dealing with chitin and chitosan nanofibrils. In fact, the partially re-acetylated chitosan (degree of acetylation 0.23) is promptly depolymerized by lysozyme, papain, and lipase thanks to the ideal degree of acetylation for maximum enzymatic activity. Remarkably, the re-acetylated... 

Fig. 1 Absidia chitosan after isolation in NaOH (250 g/kg), as observed at the optical microscope after staining with saphranine (scale bar. 10 pm). When re-acetylated to a degree of acetylation of 0.23, this chitosan, besides being soluble in the usual pH range for chitosans, is exceptionally soluble at pH values over 9. This work introduced the concept that an extended surface area of the carbohydrate polymer leads to enhanced performance. Reprinted from Carbohydrate Polymers 25 [29]. Copyright (1994) with permission from Elsevier...

Surface modifications of particles which are commonly used as materials for chromatography, as pigments or fillers are of considerable technical interest. By the selection of appropriate monomers and their surface polymerization different chemical functionalities or physical properties are introduced. Silica gel with an extended surface area (Si 60, E. Merc)c) is a useful substrate for the study of photoinitiated surface polymerizations )3ut less porous particles, microcrystalline materials or filjers are the objects of investigations with a more practical bacltground. 

We have also provided evidence that the behavior of microorganisms in confined micro-environment is substantially different and that their desired metabolic activities can be maximized through the modification of the surface characteristics as well as the size of the pores. These characteristics can therefore be utilized in BI as well as in the enhancement of cell penetration and cell proliferation in tissue engineering and when such polymers are grafted. Micro-fabrication technique has also been used in the development of highly porous catalysts with arterial channels feeding nano-pores which provide an extended surface area. Such materials can be used as micro-reactors as well as catalysts. 

Electrophoresis is most commonly performed in a slab gel format, which can be used in either the vertical or the horizontal configuration. Slab gels are relatively easy to form and provide a mechanically stable medium with an extended surface area to reduced thermal convection (though they are vastly inferior to capillaries in this regard - see following section). It is possible to excise separated bands from a gel, and thus perform batch separations using electrophoresis. 

One way to minimize the adverse effect of controlling resistance is to use extended surface area to offset the effect. Another way is to increase the velocity... 

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