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Coated substrates involve different materials such as coated credit cards, paper, woven and nonwoven textiles, plastic or aluminum films and sheets, and roll coverings. Calender lines can process one coated side, both sides, or laminated (multiple substrates coated between each substrate). Calender with three rolls is usually sufficient for one-sided coating. However four rolls are used for extremely thin coatings. The 4-roll calender can be used for double-sided coating that is applied simultaneously on both sides. Specialized calendering equipment is used for certain products such as credit cards, floor tiles, and window curtains. [Pg.379]

Manufacturers Comments One side special dispersion adhesive, solvent free. Water-based acrylic dispersion. Flexible with very high initial tack. [Pg.91]

Special configurations to reduce probe wobble and sensitivity to geometry changes and to allow inspection nearby both sides of a support plate in one pass... [Pg.323]

To clear up a role of two-side filling with liquids of dead-end capillaries in the practice of PT, we ve carried out some special experiments. It was established some years ago that it s almost impossible to reveal small defects applying dry powder developer in the case when defect s hollows are completely filled with a penetrant. But just such a situation one... [Pg.617]

The measuren.cnts are performed on a sample made from Inconell IN 718 placed at our disposal by Me oren- und Turbinen-Union Miinchen GmbH (MTU). The sample is of disk shape and has a curved side and a flat side, see also fig. 6. On the curved side MTU had detected a segregation reaching to the surface but with unknown depth. It had been detected by segregation etching and its existence was confirmed by eddy current testing. Both methods are successful only in such a special case where the segregation extends to the surface. [Pg.990]

As discussed above, the nonlinear material response, P f) is the most connnonly encountered nonlinear tenn since vanishes in an isotropic medium. Because of the special importance of P we will discuss it in some detail. We will now focus on a few examples ofP spectroscopy where just one or two of the 48 double-sided Feymnan diagrams are important, and will stress the dynamical interpretation of the signal. A pictorial interpretation of all the different resonant diagrams in temis of wavepacket dynamics is given in [41]. [Pg.260]

Chemistry, like any scientific discipline, relies heavily on experimental observations, and therefore on data. Until a few years ago, the usual way to publish information on recent scientific developments was to release it in books or journals. In chemistry, the enormous increase in the number of compounds and the data concerning them resulted in increasingly ineffective data-handling, on the side of the producers as well as the users. One way out of this disaster is the electronic processing, by computer methods, of this huge amount of data available in chemistry. Compared with other scientific disciplines that only use text and numbers for data transfer, chemistry has an additional, special challenge molecules. The molecular species consist of atoms and bonds that hold them together. Moreover, compounds... [Pg.15]

Reflux Distillation Unit. The apparatus shown in Fig. 38 is a specially designed distillation-unit that can be used for boiling liquids under reflux, followed by distillation. The unit consists of a vertical water-condenser A, the top of which is fused to the side-arm condenser B. The flask C is attached by a cork to A. This apparatus is particularly suitable for the hydrolysis of esters (p. 99) and anilides (p. 109), on a small scale. For example an ester is heated under reflux with sodium hydroxide solution while water is passed through the vertical condenser water is then run out of the vertical condenser and passed through the inclined condenser. The rate of heating is increased and any volatile product will then distil over. [Pg.64]

Synthesis of large heterocycles usually involves condensation reactions of two difunctional molecules. Such molecules tend to polymerize. So far two special techniques have been described above to avoid this important side-reaaion , namely high dilution and use of templates. The general procedure to avoid polymerizations in reactions between difunctional molecules is, of course, the application of protecting groups as described in sections 4.1.2 and 2.6. [Pg.248]

Chapters 9, 10 and 11 describe methods for substitution directly on the ring with successive attention to Nl, C2 and C3. Chapters 12 and 13 are devoted to substituent modification as C3. Chapter 12 is a general discussion of these methods, while Chapter 13 covers the important special cases of the synthesis of 2-aminoethyl (tryptaminc) and 2-aminopropanoic acid (tryptophan) side-chains. Chapter 14 deals with methods for effecting carbo cyclic substitution. Chapter 15 describes synthetically important oxidation and reduction reactions which are characteristic of indoles. Chapter 16 illustrates methods for elaboration of indoles via cycloaddition reactions. [Pg.4]

One of the virtues of the Fischer indole synthesis is that it can frequently be used to prepare indoles having functionalized substituents. This versatility extends beyond the range of very stable substituents such as alkoxy and halogens and includes esters, amides and hydroxy substituents. Table 7.3 gives some examples. These include cases of introduction of 3-acetic acid, 3-acetamide, 3-(2-aminoethyl)- and 3-(2-hydroxyethyl)- side-chains, all of which are of special importance in the preparation of biologically active indole derivatives. Entry 11 is an efficient synthesis of the non-steroidal anti-inflammatory drug indomethacin. A noteworthy feature of the reaction is the... [Pg.61]

The best procedures for 3-vinylation or 3-arylation of the indole ring involve palladium intermediates. Vinylations can be done by Heck reactions starting with 3-halo or 3-sulfonyloxyindoles. Under the standard conditions the active catalyst is a Pd(0) species which reacts with the indole by oxidative addition. A major con.sideration is the stability of the 3-halo or 3-sulfonyloxyindoles and usually an EW substituent is required on nitrogen. The range of alkenes which have been used successfully is quite broad and includes examples with both ER and EW substituents. Examples are given in Table 11.3. An alkene which has received special attention is methyl a-acetamidoacrylate which is useful for introduction of the tryptophan side-chain. This reaction will be discussed further in Chapter 13. [Pg.109]

Phenylalanine and tryptophan have side chains that incorporate aromatic rings which are large and hydrophobic The aromatic portion of tryptophan is bicyclic which makes it larger than phenylalanine Tryptophan also has a more electron rich aromatic ring and is more polarizable than phenylalanine Its role is more specialized and it is less abundant m proteins than most of the other ammo acids... [Pg.1113]

Special attention should be paid to one-sided deviation from the control limits, because systematic errors more often cause deviation in one direction than abnormally wide scatter. Two systematic errors of opposite sign would of course cause scatter, but it is unlikely that both would have entered at the same time. It is not necessary that the control chart be plotted in a time sequence. In any... [Pg.211]

However, interpretation of, or even obtaining, the mass spectrum of a peptide can be difficult, and many techniques have been introduced to overcome such difficulties. These techniques include modifying the side chains in the peptide and protecting the N- and C-terminals by special groups. Despite many advances made by these approaches, it is not always easy to read the sequence from the mass spectrum because some amide bond cleavages are less easy than others and give little information. To overcome this problem, tandem mass spectrometry has been applied to this dry approach to peptide sequencing with considerable success. Further, electrospray ionization has been used to determine the molecular masses of proteins and peptides with unprecedented accuracy. [Pg.333]

Panels for siding might be cut to resemble rough-cut lumber and grooved at intervals to show the appearance of board-on-board siding. Other treatments might include pressure-treatment with preservatives or fire-retardant chemicals for special appHcations requiring these characteristics. [Pg.384]

Humidification. For wiater operation, or for special process requirements, humidification maybe required (see Simultaneous HEAT and mass transfer). Humidification can be effected by an air washer which employs direct water sprays (see Evaporation). Regulation is maintained by cycling the water sprays or by temperature control of the air or water. Where a large humidification capacity is required, an ejector which direcdy mixes air and water in a no22le may be employed. Steam may be used to power the no22le. Live low pressure steam can also be released directly into the air stream. Capillary-type humidifiers employ wetted porous media to provide extended air and water contact. Pan-type humidifiers are employed where the required capacity is small. A water filled pan is located on one side of the air duct. The water is heated electrically or by steam. The use of steam, however, necessitates additional boiler feed water treatment and may add odors to the air stream. Direct use of steam for humidification also requires careful attention to indoor air quahty. [Pg.362]

Green coloration, present in many vegetable oils, poses a particular problem in oil extracted from immature or damaged soybeans. Chlorophyll is the compound responsible for this defect. StmcturaHy, chlorophyll is composed of a porphyrin ring system, in which magnesium is the central metal atom, and a phytol side chain which imparts a hydrophobic character to the stmcture. Conventional bleaching clays are not as effective for removal of chlorophylls as for red pigments, and specialized acid-activated adsorbents or carbon are required. [Pg.124]

A special coil configuration is used to heat thin strips of metal that caimot be heated efficiently with a coil that encircles the load, as the strip thickness is small compared to the depth of penetration. The transverse flux induction coil is positioned on either side of a strip to produce a uniformly heated strip with good efficiency in a much smaller space than conventional radiant or convective strip heating furnaces (6). [Pg.129]


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