Pleating Time

In the test for fastness to steam pleating, ISO 10S-P02, the specimen and adjacents are steamed under pressure for a specified time. The conditions used range from 5 min at 108°C and 135 kPa pressure for the mild test, to 15 min at 130°C and 270 kPa (2.66 atm) pressure for the severe test. 

Duty cycles Continuous duty (CMR) (S ) Periodic duties Factor of inertia (FI) Pleating and cooling characteristic curves Drawing the thermal curves Rating of short motors Equivalent output of short time duties Shock loading and use of a flywheel... 

The fact that a denatured protein can spontaneously return to its native conformation was demonstrated for the first time with ribonuclease, a digestive enzyme (see p. 266) consisting of 124 amino acids. In the native form (top right), there are extensive pleated sheet structures and three a helices. The eight cysteine residues of the protein are forming four disulfide bonds. Residues His-12, Lys-41 and His-119 (pink) are particularly important for catalysis. Together with additional amino acids, they form the enzyme s active center. 

Pleat and crease retention, 879 Pleochroism, 289 Ploughing, 841 Plunger forward time, 806 Pockels-effect, 349 Poiseuille flow, 591 number, 59 Poisson ratio, 383 Polar forces, 205 Polarisation, 319 flux density, 348 Polaron, 341... 

Many proteins can be made to clump into fibrous amyloid deposits like those seen in Alzheimer s disease, Creutzfeldt-Jakob disease (the human counterpart of mad cow disease), and other serious ailments. To help prove this point, a natural enzyme to convert to amyloid fibrils—insoluble protein aggregates with a /3-pleated sheet structure—simply by maintaining protein for some time in the unfolded state. Until now, scientists have generally believed that only specific proteins such as amyloid /3-protein and prions are capable of being converted into amyloid fibrils.11 A variety of spectroscopic techniques have been used to confirm the gradual development of amyloid fibrils and to verify the fibrils predominant /3-pleated sheet structure. In the partially unfolded intermediates that form under denaturing conditions, hydrophobic amino acid residues and polypeptide backbone normally buried inside fully folded structures become exposed. Further work is needed to confirm and advance these findings. 

My husband pumped faster and faster, and Sarah s athletic leg movements showed a familiarity with the rhythm that suggested they had done this many times before. Besides, her small right hand, which a few hours ago had pinned the pleat of ribbon to my bodice, had maneuvered itself between his thighs and was fingering his genitals and buttocks as if it knew exactly how to please him. 

A regular (or still time-averaged) cone conformation is discussed for cahx[5]arenes while calix[8]arenes most probably adopt a pleated loop conformation with a regular up and down arrangement of the phenolic units. 

Microfiltration membranes are similar to UF membranes but have larger pores. Microfiltration membranes are used to separate particles in the range of 0.02-10 pm from liquid or gas streams. Commercial MF membranes are made from a wide variety of materials including polymers, metals, and ceramics. A wide variety of membrane module designs are available including tubular, spiral wound, pleated sheet, hollow fiber, and flat sheet designs. Some modules are best suited for crossflow filtration, and others are designed for dead-end filtration. In dead-end filtration, the feed liquid flows normal to the surface of the membrane, and retained particles build up with time as a cake layer on the membrane surface or within the pores of the membrane. 

Incidentally, this also explains how "capillary-pore" membrane cartridges can equal the throughput of "tortuous-pore" cartridges. Two to three times the area of the "tortuous-pore" membranes can be pleated into a similar cartridge because the capillary-pore membranes are so much thinner. 

For reasons enumerated earlier, "capillary-pore" membranes, though pleat-able, will not yield satisfactory bubble-points and begin to pass Pseudomonas diminuta at challenge levels above 103-10s organisms even though the membrane area is 2 to 3 times greater. 

Pleated cartridges are considerably more expensive than the equivalent membrane area in 293 mm discs (2 to 4 times as much). Some users insist that the lower replacement labor does not off-set the additional expense. However, the trend is definitely towards pleated cartridges for through-flow filtration. The movement to pleated cartridges has been accelerated with the discovery that some exhausted cartridges can be reused after backwashing. 

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