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Continuous form

From equations (9.1) and (9.2), a Hamilton-Jaeobi equation may be expressed as [Pg.275]

For a linear, time invariant plant, equation (9.1) beeomes [Pg.275]

Equation (9.23) belongs to a elass of non-linear differential equations known as the matrix Rieeati equations. The eoeffieients of P(t) are found by integration in reverse time starting with the boundary eondition [Pg.276]

Kalman demonstrated that as integration in reverse time proeeeds, the solutions of F t) eonverge to eonstant values. Should t be infinite, or far removed from to, the matrix Rieeati equations reduee to a set of simultaneous equations [Pg.276]

Equations (9.23) and (9.25) are the eontinuous solution of the matrix Rieeati equation. [Pg.276]


The radical formed m step 3 then adds to a third molecule of ethylene and the process continues forming a long chain of methylene groups... [Pg.268]

In this representation the FeCl2 which takes part in the first step of the reaction is not a tme catalyst, but is continuously formed from HQ. and iron. This is a highly exothermic process with a heat of reaction of 546 kj /mol (130 kcal/mol) for the combined charging and reaction steps (50). Despite the complexity of the Bnchamp process, yields of 90—98% are often obtained. One of the major advantages of the Bnchamp process over catalytic hydrogenation is that it can be mn at atmospheric pressure. This eliminates the need for expensive high pressure equipment and makes it practical for use in small batch operations. The Bnchamp process can also be used in the laboratory for the synthesis of amines when catalytic hydrogenation caimot be used (51). [Pg.262]

Many different thermosetting polymers are used in pultmsion, eg, polyester, vinyl ester, epoxy, and urethane. Reinforcements must be in a continuous form such as rovings, tows, mats, fabrics, and tapes. Glass fibers are the low cost, dominant composition, but aramid and carbon fibers are also used. [Pg.96]

The left-hand end of the activated monomer is sealed off by the OH terminator, but the right-hand end (with the star) is aggressively reactive and now attacks another ethylene molecule, as we illustrated earlier in Fig. 22.1. The process continues, forming a longer and longer molecule by a sort of chain reaction. The —OH used to start a chain will, of course, terminate one just as effectively, so excess initiator leads to short chains. As the monomer is exhausted the reaction slows down and finally stops. The DP depends not only on the amount of initiator, but on the pressure and temperature as well. [Pg.255]

Sodium and potassium are restricted because they react with sulfur at elevated temperatures to corrode metals by hot corrosion or sulfurization. The hot-corrision mechanism is not fully understood however, it can be discussed in general terms. It is believed that the deposition of alkali sulfates (Na2S04) on the blade reduces the protective oxide layer. Corrosion results from the continual forming and removing of the oxide layer. Also, oxidation of the blades occurs when liquid vanadium is deposited on the blade. Fortunately, lead is not encountered very often. Its presence is primarily from contamination by leaded fuel or as a result of some refinery practice. Presently, there is no fuel treatment to counteract the presence of lead. [Pg.443]

The existence of unbalance in a rotor system may be in continuous form or discrete form, as shown in Figure 17-2. Ascertaining an exact distribution is an extremely difficult, if not impossible, task by today s techniques. [Pg.587]

The mode of action of plasticizers can be explained using the Gel theory [35 ]. According to this theory, the deformation resistance of amorphous polymers can be ascribed to the cross-links between active centres which are continuously formed and destroyed. The cross-links are constituted by micro-aggregates or crystallites of small size. When a plasticizer is added, its molecules also participate in the breaking down and re-forming of these cross-links. As a consequence, a proportion of the active centres of the polymer are solvated and do not become available for polymer-to-polymer links, the polymer structure being correspondingly loosened. [Pg.627]

If the failure distribution of a component i.s exponential, the conditional probability of observing exactly M failures in test time t given a true (but unknown) failure rate A and a Poisson distribution, is equation 2.6-9. The continuous form of Bayes s equation is equation... [Pg.52]

The time evolution of the discrete-valued CA rule, F —> F, is thus converted into a two-dimensional continuous-valued discrete-time map, 3 xt,yt) —> (a y+i, /y+i). This continuous form clearly facilitates comparisons between the long-time behaviors of CA and their two-dimensional discrete mapping counter-... [Pg.200]

We give both forms here because, depending on the problem, either of the two forms may yield a simpler answer. Although the discrete form may appear a-priori to be the natural choice, for example, its discrete nature actually introduces some spurious periodicity into the resulting power spectra, thus washing away some of its characteristic features. We therefore follow Li [H87] in working mainly with the continuous forms of R t) and... [Pg.305]

Using equation 6.16 we obtain the (continuous form of the) power spectrum ... [Pg.308]

The kinetics and mechanism of living radical polymerization have been reviewed by Fischer,21 Fukuda et at.,22 and Goto and Fuktida.23 In conventional radical polymerization, new chains are continually formed through initiation w hile existing chains are destroyed by radical-radical termination. The steady state concentration of propagating radicals is 10"7 M and an individual chain will have a lifetime of only 1-10 s before termination within a total reaction lime that is... [Pg.454]

In 50 mL of perchloroethylene is dissolved 1.5 mL of sebacyl chloride 2.2 g of hexamethylenediamine and 4.0 g of sodium carbonate are dissolved in 50 mL water. The aqueous solution is placed carefully on the perchloroethylene solution in a 200-rnL tail-form beaker or similar vessel (Fig. 3.17). A film is immediately formed at the interface. The film is grasped with tweezers and raised as a rope of continuously forming polymer film. The rope is guided over two glass rods with a 1-mm drop. With this setup, speeds up of 5 m/min can be attained for 8 min. [Pg.171]

A striking feature of the cellular automata (CA) models is that they treat not only the ingredients, or agents, of the model as discrete entities, as do the traditional models of physics and chemistry, but now time (iterations) and space (the cells) are also regarded as discrete, in stark contrast to the continuous forms for these parameters assumed in the traditional, equation-based models. In practice, as we shall see, this distinction makes little or no difference, for the traditional continuous results appear, quite naturally, as limiting cases of the discrete CA analyses. Nonetheless, this quantization of time and space does raise some interesting theoretical and philosophical questions, which we shall, however, ignore at this time. ... [Pg.11]

Stainless steel coil and sheet stock is unloaded and stored outdoors under protective cover. As it is needed, the coil stock is moved indoors by a forklift to one of six automatic tube mills where the sides of unrolled metal strips are curled up to form a continuous, cylindrical pipe. The seam of the resulting pipe is fused in an electric in-line welding operation. An abrasive saw is used to cut the continuously formed pipe to specified lengths sections of poorly welded pipe are cut away. [Pg.1205]

Extruders play a key role in many conversions processes we use them to melt solid polymers and pump the resulting molten material to a die or a mold. After the molten polymer has been molded to the desired shape, it is cooled to form a solid product. We can feed the output of an extruder to continuous forming processes to create films, pipes, and fibers. Alternatively, we can employ discontinuous molding processes to create discrete items, such as soda bottles, lenses for single use cameras, or bathtubs. [Pg.213]

Abstract. We have studied the effects of an hypothetical initial generation made only of very massive stars (M > 100M , pair-creation SNe) on the chemical and photometric evolution of spheroidal systems. We found that the effects of Population III stars on the chemical enrichment is negligible if only one or two generations of such stars occurred, whereas they produce quite different results from the standard models if they continuously formed for a period not shorter than 0.1 Gyr. In this case, the results produced are at variance with the main observational constraints of ellipticals such as the average [< a/Fe > ] ratio in stars and the color-magnitude diagram. [Pg.373]

A convenient concept for introducing the surface boundary condition into the mathematical formulation of migration theory is that of what may be called a diffusional offset length d. Suppose that the external and surface conditions are describable by a set of parameters X, which we do not need to specify in detail we also allow the surface conditions to depend on the internal hydrogen concentration just beneath the surface. If the hydrogen complexes that are continually forming in the crystal are sufficiently immobile, the balance between inflow and outflow across the surface will depend only on X and on the concentration no(0) of H0 just beneath the surface. (If mobile H+ or H are present, the statement just... [Pg.284]

NMR. Proton NMR is obviously likely to give an enormous range of signals from a typical confectionery product. An NMR instrument to analyse water in foods has to be a low-resolution instrument, whether of the original continuous form or of the later pulsed type. The aim is to discriminate between the protons in water and those in other molecules. Fortunately, this is not too difficult. [Pg.21]


See other pages where Continuous form is mentioned: [Pg.81]    [Pg.371]    [Pg.233]    [Pg.318]    [Pg.265]    [Pg.336]    [Pg.270]    [Pg.436]    [Pg.55]    [Pg.95]    [Pg.439]    [Pg.518]    [Pg.441]    [Pg.80]    [Pg.207]    [Pg.274]    [Pg.280]    [Pg.818]    [Pg.17]    [Pg.509]    [Pg.251]    [Pg.326]    [Pg.93]    [Pg.39]    [Pg.532]    [Pg.305]    [Pg.153]    [Pg.149]   


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