Bonded sheet lining

Solid sheet linings can also be applied either as an adhesive-bonded lining or a loose-fitting lining. Adhesive-bonded sheet linings on steel substrates consist of fabric backed sheets bonded to steel vessel walls with neoprene or epoxy based adhesive. Linings may be applied in the field or in the shop. Joints are heat welded using a rod of the same polymer as the sheets. 

Some adhesive bonded sheet lined vessels have been rated to withstand full vacuum at ambient temperature. Vacuum ratings may vary with vessel size. 

Figure 2.6. The tetrahedral structures of ice (a), (fc) are planes through sheets of selected oxygen nuclei (open circles), hydrogen nuclei (shotm in the insert as solid circles) are not shown in the main drawing. The insert illustrates the overlap of oxygen line pairs and the hydrogen nuclei, thus forming the hydrogen bonds (dotted lines)...

Fig. 3.—Parallel packing arrangement of the 2-fold helices of cellulose I (1). (a) Stereo view of two unit cells approximately normal to the ac-plane. The two comer chains (open bonds) in the back, separated by a, form a hydrogen-bonded sheet. The center chain is drawn in filled bonds. All hydrogen bonds are drawn in dashed lines in this and the remaining diagrams, (b) Projection of the unit cell along the c-axis, with a down and b across the page. No hydrogen bonds are present between the comer and center chains.

Fig. 8 Proposed model for gramicidin S in a membrane according to the orientational constraints obtained from and N-NMR. The upright backbone alignment (r 80°) and slant of the /3-sheets (p -45°) are compatible with the formation of an oligomeric /3-barrel that is stabilized by hydrogen bonds (dotted lines). A The oligomer is depicted sideways from within the lipid bilayer interior (showing only backbone atoms for clarity, but with hydrophobic side chains added to one of the monomers). Atomic coordinates of GS were taken from a monomeric structure [4], and the two DMPC lipid molecules are drawn to scale (from a molecular dynamics simulation coordinate file). The bilayer cross-section is coloured yellow in its hydrophobic core, red in the amphiphilic regions, and light blue near the aqueous surface. B Illustrates a top view of the putative pore, although the number of monomers remains speculative...

Shown in the upper panel of Scheme 2 is the top view of the GS14 backbone showing the positions of potential H-bonds (dashed lines) in each five-residue p-strand and the two type II p-turns defined by the D-Tyr-Pro sequence which link the two P-strands. The side view of GS14 (2) is shown in the lower panel of Scheme 2 where the P-sheet structure of the backbone is evident and the relative orientation of successive side chains within the 3-strands can be seen. The P-sheet structure gives GS14 (2) a highly amphipathic nature with a large hydrophobic face made up of Val and Leu residues and a basic face made up of Lys residues. 

Fig. B.8.2. Double-stranded antiparallel //-sheet with intermolecular hydrogen bonds (dotted lines) [4],...

Figures 14 Stereopacking of 7 and 8 with cell edges outlined O, white N, grey C, black H-bonds, dotted line. For all left-handed members of stereopairs, the view is along the short cell edge b (ca 5.3 A) defined by a 1,3-distance of the puckered H-bonded super-arsenic sheets [28].

Figure 4.30. ORTEP drawing of the hydrogen-bond sheet formed by (9-H) molecules in FAKHOO. The dotted lines represent hydrogen bonds.

Polypropylene sheet appeared in the 1950s, first as a plain white sheet, then, like the early PVC sheet, with a fabric backing laminated to it. No effective bonding agent was ever found for this material, and this author has not heard of its use in this manner for a number of years. However, there is available a sheet lining material having a sheet of polypropylene laminated to a sheet of natural or synthetic rubber to provide an adhesive accepting surface. 

Fig. (8). Representation of the main structural characteristics of peptides with a p-hairpin fold. Peptides are formed by antiparallel two-strand P-sheet stabilized by several hydrogen bonds (hatched lines) and by disulphide bridges. Modified with permission from [109]. Copyright (2002) Research Signpost.

Description Rubber Linings Thin Plastic Linings Glass-reinforced Plastic Linings Sheet Linings (Adhesively Bonded) Proprietary... 

Fig. 7.4. Examples of (a) parallel and (b) antiparallel 3-pleated sheets, shown with only two chains, that are held together by H-bonds (dashed lines). Note the difference in the H-bonds in the parallel (slanted and regularly spaced) and antiparallel (perpendicular with alternating wide and narrow spacing) sheets. (Adapted from Horton HR, Moran LA, Ochs RS, et al. Principles of Biochemistry. Englewood Cliffs, NJ Neil Patterson Publishers/Prentice Hall, 1993 with permission.)...

During World War II, synthetic rubber and resin-modified phenolics were used to bond aluminum sheets (available only in in. thickness at that time) into billets from which airplane propellers were carved, thus replacing laminated wood, which often shattered on impact with a bullet. Similar adhesives were used to bond rubber to metal in a variety of vibration-damping applications. The most successful widely known product of the new technology was the automotive bonded brake lining first introduced in 1947, and now regarded as a symbol of quality and integrity [12, p. 490]. 

Fig. 4.20 Hydrogen-bonded sheets in (a) nylon-6,6 and (b) nylon-6. The unit-cell faces are shown by the dashed lines. (Reprinted by Permission of John Wiley Sons, Inc.)...

Fig. 4.21 The stacking of the hydrogen-bonded sheets in the a and p crystalline forms of nylon-6,6. The lines represent the chains and the circles the oxygen atoms. Full and broken circles represent atoms on the near and far sides of the chain, respectively. The dashed lines show the unit cell. (Reproduced by permission of the Royal Society.)...

Fig. 21.3 Projections of the crystal structures of cellulose IR left) and la (right) down the chain axes (top), perpendicular to the chain axis and in the plane of the hydrogen bonded sheets (middle), and perpendicular to the hydrogen boned sheets (bottom). The cellulose chains are represented by red skeletal models. The asymmetric unit of each structure is also represented in thicker lines with carbons in yellow. The unit cell of each structure is shown in white. Reproduced with permission from Nishiyama et al. (2003a). Copyright 2003, American Chemical Society...

Fluoropolymer linings are installed using adhesive bonded fabric-backed sheets, sprayed dispersions, rotolining, electrostatic sprayed powders and by mechanically attaching loose sheet linings. 

Thermoplastic sheet linings are used more extensively than any other type of lining. Table 3.1 lists the most common thermoplasts used as linings. These materials are used to line piping as well as vessels. They may be installed as a loose lining or as a bonded lining. 

Unplasticized PVC cannot be bonded directly to a metal substrate, while plastisols (type 2 PVC) can be bonded directly. Because of this, many PVC sheet linings are dual laminates with an unplasticized PVC sheet bonded to a plastisol. This dual laminate can then be bonded to the metal substrate, leaving the unplasticized PVC sheet exposed to the eorrodent. 

Figure 26-3 (A) The pleated sheet, or /8 configuration, which is held in place by hydrogen bonds (dotted lines) between two polypeptide strands. (After Proteins, by Paul Doty, Scientific American, September 1957. Copyright 1957, Scientific American, Inc.) (B) The peptide bonds define the individual pleats (shaded in yellow) the positions of the side chains, R, are alternately above and below the planes of the sheets. The dotted lines indicate hydrogen bonds to a neighboring chain or to water.

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