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The Final Stage

Repeated tumbling in sawdust removes unwanted residue. A final glazing, ironing, or spraying with a chemical and air blowing puts a sheen on the finished fur. The wool of sheep and other skins with dull and crimped hair can be stretched and made more lustrous by ironing on a special machine. It is brushed with water and some acetic acid and alcohol then ironed for a short time at ca. 200 °C. [Pg.449]

When the dressing process is complete, the pelts emerge as shiny, silky fur and soft, supple leather. Some furs go through additional beautification steps. Coarse guard hair, for example, from beaver and Alaska fur seal, is removed by plucking. To brighten furs, fluorescent dyes are used. [Pg.449]

The remaining fur fiber is then sheared with revolving blades to a velvety texture. Nutria, some rabbit, and muskrat may also be sheared to imitate seal. Pointing , a process of gluing either badger or monkey guard hair into furs, adds [Pg.449]


All too often safety and health (and environmental) considerations are left to the final stages of the design. Returning to the hierarchy of design illustrated by the onion diagram in Fig. 1.6, such considerations would add another layer in the diagram outside the utilities layer. This approach leaves much to be desired. [Pg.255]

Following this hierarchy, all to often safety, health and environmental considerations are left to the final stages of design. This approach leaves much to be desired, since early decisions made purely for process reasons often can lead to problems of safety, health, and environment that require complex solutions. It is better... [Pg.399]

The preceding conclusion is easily verified experimentally by arranging two bubbles with a common air connection, as illustrated in Fig. II-2. The arrangement is unstable, and the smaller of the two bubbles will shrink while the other enlarges. Note, however, that the smaller bubble does not shrink indefinitely once its radius equals that of the tube, its radius of curvature will increase as it continues to shrink until the final stage, where mechanical equilibrium is satisfied, and the two radii of curvature are equal as shown by the dotted lines. [Pg.5]

The final stage of compiling a maximally refined dataset is to split it into a training and test dataset. The definition of a test dataset is an absolute must during learning, as, in fact, it is the best way to validate the results of that learning. [Pg.205]

The metal is isolated commercially by a complex chemical process, the final stage of which is the hydrogen reduction of ammonium ruthenium chloride, which yields a powder. The powder is consolidated by powder metallurgy techniques or by argon-arc welding. [Pg.108]

Synthesis The final stages are very similar to Review Problem 20 (frames 212-3). TM 249 is an intermediate in Stork s synthesis of Aspidosperma alkaloids. Stork s method was actually a variation on the one we have proposed ( J. Amer. Chem. Soc., 1963, 85, 2872) ... [Pg.80]

Of all the topics discussed in this text, mesoscale simulations are probably at the most infantile stage of development. The idea of the mesoscale calculations is very attractive and physically reasonable. However, it is not as simple as one might expect. The choice of bead sizes and parameters is crucial to obtaining physically relevant results. More complex bead shapes are expected to be incorporated in future versions of these techniques. When using one simulation technique to derive parameters for another simulation, very small errors in a low-level calculation could result in large errors in the final stages. [Pg.275]

Sote 1. In the final stage of the distillation the remaining liquid is subjected to a relatively higli temperature. This causes dimerization of the greater part of the yne-allene RCeC-CH=C=CH2, which is formed as a by product. [Pg.72]

During the final stage of the distillation, water from the bath was poured along the column in order to minimize the hold-up. Most of the product passed over between... [Pg.126]

The major disadvantage of solid-phase peptide synthesis is the fact that ail the by-products attached to the resin can only be removed at the final stages of synthesis. Another problem is the relatively low local concentration of peptide which can be obtained on the polymer, and this limits the turnover of all other educts. Preparation of large quantities (> 1 g) is therefore difficult. Thirdly, the racemization-safe methods for acid activation, e.g. with azides, are too mild (= slow) for solid-phase synthesis. For these reasons the convenient Menifield procedures are quite generally used for syntheses of small peptides, whereas for larger polypeptides many research groups adhere to classic solution methods and purification after each condensation step (F.M. Finn, 1976). [Pg.237]

Figure 5.3 shows the data for the uncatalyzed polymerization of adipic acid and 1,10-decamethylene glycol at 161°C plotted according to Eq. (5.21). The various provisos of the catalyzed case apply here also, so it continues to be appropriate to consider only the final stages of the conversion to polymer. From these results, k is about 4.3 X 10" kg eq min at 161°C. [Pg.289]

In the final stage of this involved derivation, we have to free Eq. (10.78) from the dependence it contains on the geometry of Fig. 10.11. The problem lies in the dot product of the vector rj, -which replaces OP in Fig. 10.11-and... [Pg.700]

Note that seven figures are retained in the calculation until the final stage, when the numbers are rounded to six significant figures. [Pg.6]

Note that, since 5q is given, effectively, to six significant figures, the calculation has been done to seven figures and rounded to six at the final stage. [Pg.134]

Retrofitting features of the more efficient reactor types have been the principal thmst of older methanol plant modernization (17). Conversion of quench converters to radial flow improves mixing and distribution, while reducing pressure drop. Installing an additional converter on the synthesis loop purge or before the final stage of the synthesis gas compressor has been proposed as a debotdenecking measure. [Pg.280]

Anhydrous Milk Fat. One high milk-fat material is butter oil (99.7% fat), also called anhydrous milk fat or anhydrous butter oil if less than 0.2% moisture is present. Although the terms are used iaterchangeably, anhydrous butter oil is made from butter and anhydrous milk fat is made from whole milk. For milk and cream there is an emulsion of fat-ia-semm, for butter oil and anhydrous milk fat there is an emulsion of semm-ia-fat, such as with butter. It is easier to remove moisture ia the final stages to make anhydrous milk fat with the semm-ia-fat emulsion. [Pg.367]

The three basic types of size reduction circuits used to produce a fine product ate shown in Eigure 1. The final stages of the grinding circuit are typically operated in closed circuit, at comparatively high circulating loads, so that the material has tittle chance of being broken a second time before it is removed from the circuit by a classifier. Rod mills are operated normally in an open circuit. [Pg.396]

The polyestetification reaction is carried out in the presence of an inert gas, such as nitrogen or carbon dioxide, to prevent discoloration. Usually, the sparge rate of the inert gas is increased in the final stages of polyestetification to assist the removal of residual water. Although the removal of water can be facihtated by processing under vacuum, this is rarely used on a commercial scale. [Pg.314]

Viscosity. Because a clump of particles contains occluded Hquid, the effective volume fraction of a suspension of clumps is larger than the volume fraction of the individual particles that is, there is less free Hquid available to faciHtate the flow than if the clumps were deagglomerated. The viscosity of a suspension containing clumps decreases as the system becomes deagglomerated. This method is not very sensitive in the final stages of deagglomeration when there are only a few small clumps left. [Pg.548]

In thermoelectric cooling appHcations, extensive use has been made of cascaded systems to attain very low temperatures, but because the final stage is so small compared to the others, the thermal flux is limited (Eig. 3). The relative sizes of the stages ate adjusted to obtain the maximum AT. Thus, for higher cooling capacity, the size of each stage is increased while the area ratios ate maintained. [Pg.505]

The stmctures of selected cephalosporins on the U.S. market, or in the final stages of development, are shown in Tables 4—8 (see also 78, 87). For every cephalosporin which has made it to the marketplace, HteraHy thousands of analogues were synthesized in order to estabUsh the stmcture-activity profile and allow selection of a clinical candidate. In addition to these compounds, there is a tremendous number of cephalosporin compounds currendy at various stages of development. A more extensive listing of the newer cephalosporins under preclinical or clinical evaluation may be found in a number of reviews (79,88). [Pg.28]

Further Preparative Reactions. When pulps are to be used in the production of materials that do not retain the original fiber stmcture, such as rayon or ceUulose acetate film, the lignin, hemiceUulose, and other components must be reduced to the lowest possible concentrations. A surfactant (ionic or nonionic) is often added during a hot, weakly alkaline extraction step after chlorination. Another approach, sometimes used in addition to the surfactant step, is to treat the pulp with 6—10% NaOH after most of the oxidative bleaching is finished. This treatment removes most of the hemiceUulose. In most purification plants the final stage includes use of sulfuric acid chelators are optional. [Pg.238]

Specific advancements ia the chemical synthesis of coUoidal materials are noteworthy. Many types of genera ting devices have been used to produce coUoidal Hquid aerosols (qv) and emulsions (qv) (39—43) among them are atomizers and nebulizers of various designs (30,44—50). A unique feature of produciag Hquid or soHd coUoids via aerosol processes (Table 3) is that material with a relatively narrow size distribution can be routinely prepared. These monosized coUoids are often produced by relying on an electrostatic classifier to select desired particle sizes ia the final stage of aerosol production. [Pg.395]


See other pages where The Final Stage is mentioned: [Pg.318]    [Pg.929]    [Pg.301]    [Pg.485]    [Pg.12]    [Pg.206]    [Pg.204]    [Pg.415]    [Pg.699]    [Pg.109]    [Pg.256]    [Pg.260]    [Pg.88]    [Pg.89]    [Pg.529]    [Pg.532]    [Pg.583]    [Pg.46]    [Pg.343]    [Pg.298]    [Pg.316]    [Pg.473]    [Pg.240]    [Pg.392]    [Pg.84]    [Pg.522]    [Pg.365]    [Pg.388]   


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