Reassembly

Figure Bl.3.7. A WMEL diagram for the seventh order Raman echo. The first two field actions create the usual Raman vibrational coherence which dephases and, to the extent that inliomogeneity is present, also weakens as the coherence from different cliromophores walks oflP. Then such dephasing is stopped when a second pair of field actions converts this coherence into a population of the excited vibrational state / This is followed by yet another pair of field actions which reconvert the population into a vibrational coherence, but now one with phase opposite to the first. Now, with time, the walked-oflP component of the original coherence can reassemble into a polarization peak that produces the Raman echo at frequency oi = 2(o - (O2...

Normal ions (M+, Fj+,. .., F +) in a spectrum can provide a molecular structure for substance M if the fragments can be theoretically reassembled. The problem is rather like deducing an original jigsaw puzzle by putting the pieces together correctly. For most molecules containing more than a few atoms, this reassembly exercise is difficult and often problematic. 

To carry out the reassembly exercise, connectivities between the ions must be determined. For example, does the ion Fj+ come from M+ or F/ or F2+ This process can be likened to completing a jigsaw by finding where and how the pieces fit together. 

Sticky waxes are used as thermoplastic cements. The broken pieces of a plaster impression are reassembled and held in position with sticky wax. Broken denture bases may be held in proper alignment for repair. Orthodontic apphances may be assembled with a sticky wax prior to investing and soldering. Plaster splints may be sealed to stone models in the production of porcelain or resin facings. Thus, sticky wax is useflil in almost any operation where it is desired to position and hold several small pieces in a temporary relationship. 

Since electrodialysis membranes are subject to fouling, it is sometimes necessaiy to disassemble a stack for cleaning. Ease of reassembly is a feature of ED. 

Bearings and seals shall be removed, inspeeted, and reassembled after the meehanieal running test is eompleted. If the bearings or seals require replaeement, both parties will mutually deeide if a retest is required. 

A mechanic must be supplied with the proper tools to facilitate his jobs. Many special tools are required for different machines, so as to ensure proper disassembly and reassembly. Torque wrenches should be an integral part of his tools, as well as of his vocabulary. 

On reassembly, care should be taken to return the tilting-pad and support-ball combination to the original location in the support ring. Changes in clearance and concentricity can result if the tilting-pad and support-ball combination is not returned to the same location. An eccentricity of as little as one mil can cause severe vibration problems. 

Stemmer, W.P.C. DNA shuffling by random fragmentation and reassembly In vitro recombination for molecular evolution. Proc. Natl. Acad. Sci. USA 91 10747-10751, 1994. 

Parallam, or laminated strand lumber (LSL) is a beam made by a continuous manufacturing process composed of bigger-size wood needles (very elongated wood particles) reassembled with a structural exterior grade adhesive, the favorite adhesive being isocyanates (pMDI) when heat-curing and PRFs when cold-curing. 

In reassembling the cassette assembly, remember to add the unweighed backup pad. 

It is critical npon reassembly to check that all gaskets are properly installed and that the element is correctly aligned in the honsing to ensnre that there is no bypassing of the element. Failnre to do this may resnlt in complete loss of protection. 

It is important that the inspection and maintenance activities be docn-mented as reqnired per company practice and any process safety management regnlatory reqnirements. Maintenance records shonld indicate the inspection resnlts and the scope of maintenance work performed, if any. Before the flame arrester is reinstalled in the process, it shonld be visnally inspected to make snre that reassembly conforms to the mannfactnrer s recommendations. Some companies affix a tag to the flame arrester indicating the inspection and maintenance date. 

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