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Processing sawing

The states of Europe have a deep history of pharmacopeial activity that even now is evidenced in publications by the United Kingdom, Denmark, Sweden, Spain, and Russia that date from the late 18th century. European unification as a modern process saw the creation of a common drug standard in 1964. The European Pharmacopoeia (EP) grew out of subsequent discussions within the European Economic Committee to establish a common set of rules and guidelines for the quality of drugs among the member states. [Pg.70]

Initially, batch chemical processing saw a need for extending shift operations beyond one shift operation only when the process needs dictated. [Pg.289]

The process "Sawing" still has to be completed in the past. This, too, is impossible ... [Pg.79]

About four months after beginning the implementation of the action plan, they saw a shift in the mean recordable rate from about 10 to about 4.2. This represents a 68 percent reduction. Another investigator, using our survey and a similar process, saw a reduction in the lost-time rate of over 50 percent (O Toole 2002). [Pg.173]

METHOD 4 This is a P2P recipe that Strike has no hand in. Strike never even knew about it until Strike saw everybody talking about it on the net. But it seems to be extremely popular. Shulgin has written about it. Uncle Fester, Strike understands, has written about it. And there seems to be a lot of posts regarding its high success rates. Most people get started from the method description in the patent literature where they were first published. The following are some representative examples from the U.S. Patent 4,638,094 Process for Producing Phenylacetones ... [Pg.82]

Two kinds of slarlmg materials have been examined m nucleophilic subslilulion reac lions lo Ihis poinl In Chapter 4 we saw lhal alcohols can be converted lo alkyl halides by reaclion wilh hydrogen halides and pointed oul lhal Ihis process is a nucleophilic sub slilulion lakmg place on Ihe prolonaled form of Ihe alcohol wilh water serving as Ihe... [Pg.350]

The assumption that k values are constant over the entire duration of the reaction breaks down for termination reactions in bulk polymerizations. Here, as in Sec. 5.2, we can consider the termination process—whether by combination or disproportionation to depend on the rates at which polymer molecules can diffuse into (characterized by kj) or out of (characterized by k ) the same solvent cage and the rate at which chemical reaction between them (characterized by kj.) occurs in that cage. In Chap. 5 we saw that two limiting cases of Eq. (5.8) could be readily identified ... [Pg.361]

A second way of dealing with the relationship between aj and the experimental concentration requires the use of a statistical model. We assume that the system consists of Nj molecules of type 1 and N2 molecules of type 2. In addition, it is assumed that the molecules, while distinguishable, are identical to one another in size and interaction energy. That is, we can replace a molecule of type 1 in the mixture by one of type 2 and both AV and AH are zero for the process. Now we consider the placement of these molecules in the Nj + N2 = N sites of a three-dimensional lattice. The total number of arrangements of the N molecules is given by N , but since interchanging any of the I s or 2 s makes no difference, we divide by the number of ways of doing the latter—Ni and N2 , respectively—to obtain the total number of different ways the system can come about. This is called the thermodynamic probabilty 2 of the system, and we saw in Sec. 3.3 that 2 is the basis for the statistical calculation of entropy. For this specific model... [Pg.511]

In Chap. 8 we saw how the equilibrium osmotic pressure of a solution is related to AG for the mixing process whereby the solution is formed. Any difference in the concentration of the solution involves a change in AG j, ... [Pg.685]

In Section 2.2 we saw that emission of radiation by an excited atom or molecule M may be by a spontaneous (Equation 2.4) or by an induced, or stimulated, process... [Pg.337]

An extremely important safety issue with respect to ah. wood product manufacturing processes is personal worker safety. Ah of the processes use much moving machinery, usuahy including many saws or knives. Workers must continuahy remember the inherent dangers these machines involve as weh as other possible dangerous situations which could result from malfunctions or other errors. In addition, most processes are more or less dusty and noisy. Most employers require use of safety glasses and many require hearing protection, safety shoes, and hardhats as weh as other kinds of protection needed for Specific jobs. [Pg.379]

The late 1950s saw the emergence of cast elastomers, which led to the development of reaction injection mol ding (RIM) at Bayer AG in Leverkusen, Germany, in 1964 (see Plastics processing). Also, thermoplastic polyurethane elastomers (TPUs) and Spandex fibers (see Fibers, elastomeric) were introduced during this time. In addition, urethane-based synthetic leather (see Leather-LIKEmaterials) was introduced by Du Pont under the trade name Corfam in 1963. [Pg.341]

After the wood particles are coated with resia, the particles are uniformly distributed iato a board by an air laid process. The art of the process is ia controlling and getting a uniform distribution of the wood particles by blowiag them out onto a collection chain. After forming the board shape it is moved to hot presses where the wood particles are consoHdated and the resia cured. From the hot presses the boards move to trim saws where the boards are cut square to their fiaal size. Ia some cases, the boards are sanded to final thickness and surface smoothness. [Pg.320]

Dry Ice. Refrigeration of foodstuffs, especially ice cream, meat products, and frozen foods, is the principal use for soHd carbon dioxide. Dry ice is especially useful for chilling ice cream products because it can be easily sawed into thin slabs and leaves no Hquid residue upon evaporation. Cmshed dry ice may be mixed directly with other products without contaminating them and is widely used in the processing of substances that must be kept cold. Dry ice is mixed with molded substances that must be kept cold. For example, dry ice is mixed with molded mbber articles in a tumbling dmm to chill them sufficiently so that the thin flash or rind becomes brittle and breaks off. It is also used to chill golf-ball centers before winding. [Pg.24]

Cera.mic, The ceramic substrate is made from a mixture of siUcon dioxide, talc, and kaolin to make the compound cordierite [12182-53-5]. Cordierite possesses a very low coefficient of thermal expansion and is thermal-shock resistant. The manufacturing process involves extmding the starting mixture (which is mixed with water and kneaded into a sort of dough) through a complex die to form the honeycomb stmcture. The extmded piece is dried and fired in a kiln to form the cordierite. The outside or circumferential dimension is formed by the die, and the length is cut later with a ceramic saw. [Pg.486]

As the author pointed out in the first edition of this book, the likelihood of discovering new important general purpose materials was remote but special purpose materials could be expected to continue to be introduced. To date this prediction has proved correct and the 1960s saw the introduction of the polysulphones, the PPO-type materials, aromatic polyesters and polyamides, the ionomers and so on. In the 1970s the new plastics were even more specialised in their uses. On the other hand in the related fields of rubbers and fibres important new materials appeared, such as the aramid fibres and the various thermoplastic rubbers. Indeed the division between rubbers and plastics became more difficult to draw, with rubbery materials being handled on standard thermoplastics-processing equipment. [Pg.9]

The early 1980s saw considerable interest in a new form of silicone materials, namely the liquid silicone mbbers. These may be considered as a development from the addition-cured RTV silicone rubbers but with a better pot life and improved physical properties, including heat stability similar to that of conventional peroxide-cured elastomers. The ability to process such liquid raw materials leads to a number of economic benefits such as lower production costs, increased ouput and reduced capital investment compared with more conventional rubbers. Liquid silicone rubbers are low-viscosity materials which range from a flow consistency to a paste consistency. They are usually supplied as a two-pack system which requires simple blending before use. The materials cure rapidly above 110°C and when injection moulded at high temperatures (200-250°C) cure times as low as a few seconds are possible for small parts. Because of the rapid mould filling, scorch is rarely a problem and, furthermore, post-curing is usually unnecessary. [Pg.839]


See other pages where Processing sawing is mentioned: [Pg.1029]    [Pg.341]    [Pg.96]    [Pg.206]    [Pg.319]    [Pg.319]    [Pg.173]    [Pg.568]    [Pg.190]    [Pg.1029]    [Pg.341]    [Pg.96]    [Pg.206]    [Pg.319]    [Pg.319]    [Pg.173]    [Pg.568]    [Pg.190]    [Pg.69]    [Pg.171]    [Pg.80]    [Pg.1147]    [Pg.341]    [Pg.342]    [Pg.342]    [Pg.8]    [Pg.70]    [Pg.2]    [Pg.207]    [Pg.430]    [Pg.433]    [Pg.124]    [Pg.278]    [Pg.317]    [Pg.336]    [Pg.335]    [Pg.310]    [Pg.270]    [Pg.222]    [Pg.225]    [Pg.349]    [Pg.67]    [Pg.89]   
See also in sourсe #XX -- [ Pg.101 ]




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