Plate, Imitation

Compared with the multi-scale micro mixer-tube concept (see Section 4.1.6), the total-system approach is a true mono-scale solution, and may be even termed monolithic. Integration of sensing and controlling is facile owing to the high order and repetition of construction imits (plates). 

Different from sole combinations of micro devices, this refers to a total system with many functional elements and flow-distribution and, recollecting zones, typically composed of 2-D plate-type architecture. Each of these plates usually has a separate fimction, comprising imit operations and reaction. Frequently, micro mixing and micro heat exchange fimctions and corresponding elements are employed. Often, the system can be composed of different elements resulting in different process flow combinations. Such an approach may be termed a construction kit. 

For both types of micro devices, a stainless steel frame was used as holder and Viton gaskets were applied for sealing ]72-74], A clear PMMA cover plate was also used and served for compression. This cover plate provided housing for a mini UV lamp used for irradiation. The detection imit was packaged in a similar fashion. Optical fibers were also integrated. 

Here is another application of the same principle. You see this bit of cane. I have seen boys about the streets, who are very anxious to appear like men, take a piece of cane, and light it and smoke it, as an imitation of a cigar. They are enabled to do so by the permeability of the cane in one direction, and by its capillarity. If I place this piece of cane on a plate containing... 

Figure 7 Left Surface of air bubbles (a) in whipped topping emulsion is completely covered with a thick layer of plate-siiaped fat crystals (c). w = water phase. Right Surface of air bubbles (a) of whipped imitation cream is covered with a monolayer of only slightly destabilized globules (f). Reprinted from reference 22, courtesy of Scanning Microscopy International.

Another tool is the numerical integration of the ion equations of motion. Mclver (27) and Marshall (2J3) have made use of this tool for studying some aspects of ion motion. Here, to corroborate that mass discriminating z-losses do occur, the trajectory of single ions were calculated under conditions chosen to imitate normal conditions for which symptoms of z-excitation are observed. For the calculations, the ions were started on the z-axis and were given different z-mode energies. The chirp excitation was 9.67 volts base-to-peak at each excitation plate with a 2.105 kHz/ysec sweep... 

Because best results are normally obtained with full crossflow plate operation for a sieve tray, imits may be designed with a lift valve over the hole in the plate or over a riser from the plate so that the rising gas lifts this valve to allow the vapors to be passed horizontally into the liquid as is illustrated in Fig. 16-1. This liquid cannot easily flow baek down the holes in the plate when the gas flow is low because the valve tends to close with the reduced gas flow. 

A variation of the normal sieve tray is the Turbogrid tray developed by the Shell Development Company. The Turbogrid tray uses slots instead of circular holes and operates as a counterflow plate imit with no downcomers. A typical tray consists of a flat grid of parallel slots. The slots can be stamped perforations in a flat metal sheet or the open spaces between parallel bars. 

Compact (plate or finned-tube) exchangers have 350 ft of surface area/ft of volirme, and about four times the heat transfer per cubic foot of shell-and-tube imits. 

Plate-and-frame exchangers are suited to sanitary service, and, in stainless steel, are 25-50% cheaper than shell-and-tube imits. 

In the EFISH experiment, a green light pump beam (wavelength 543.5 nm) from a helium-neon laser was used to initiate the photoisomerization of the photochromic imits. This beam was linearly polarized either in s or p polarization tuning by a A/2 plate, and the intensity for both polarizations was about 8 mW/cm. The pump beam was incident on the sample at... 

A dramatic increase in efficiency resulted from retraying column with leak-resistant valve imits, each containing a lij twei t plate located below the normal disk. 

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