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Linear formalism

The main intermediates in the pentaerythritol production reaction have been identified and synthesized (50,51) and the intermediate reaction mechanisms deduced. Without adequate reaction control, by-product formation can easily occur (52,53). Generally mild reaction conditions are favored for optimum results (1,54). However, formation of by-products caimot be entirely eliminated, particularly dipentaerytbritol and the linear formal of pentaerythritol, 2,2 -[meth5lenebis(oxymethylene)]bis(2-hydroxymethyl-1,3-propanediol) [6228-26-8] ... [Pg.465]

The quantities of formaldehyde and base catalyst required to produce pentaerythritol from 1 mol of acetaldehyde are always in excess of the theoretical amounts of 4 mol and 1 mol, respectively, and mole ratios of formaldehyde to acetaldehyde vary widely. As the mole ratio increases, formation of dipen taerytbritol and pentaerythritol linear formal is suppressed. Dipentaerythritol formation may also be reduced by increasing the formaldehyde concentration, although linear formal production increases under those conditions (55,56). [Pg.465]

The first stage crystals are rich in pentaerythritol linear formal and may be treated (60,61) to convert this species to pentaerythritol and formaldehyde, which can then be recovered. The concentrated Hquors obtained after redissolving are then recrystallized and filtered prior to drying of the final product. [Pg.465]

Quantum mechanics is very much more than just a theory it is a completely new way of looking at the world, involving a change of paradigm perhaps more radical than any other in the history of human thought" [Leggett 2002], However, the linear formalism of quantum mechanics extrapolated from the level... [Pg.499]

On the other hand, in the case = 7 we observe a different behavior. Here the non-linear values lie well below those of the linear calculation on the whole velocity range. The interpretation of these results is also very revealing. The results obtained from the dielectric calculation increase by a whole factor 49 when going from = 1 to Zj = 7 - as expected from a linear formalism. Instead, the non-linear results increase by a much smaller factor (a ratio about 20 between both maxima). This may be interpreted as a saturation in the energy loss process, i.e., the values increase by a much... [Pg.60]

This is not the case for the other two formalisms commonly used in biochemistry—the Linear Formalism and the Michaelis-Menten Formalism. The Linear Formalism implies linear relationships among the constituents of a system in quasi-steady state, which is inconsistent with the wealth of experimental evidence showing that these relationships are nonlinear in most cases. The case of the Michaelis-Menten Formalism is more problematic. An arbitrary system of reactions described by rational functions of the type associated with the Michaelis-Menten Formalism has no known solution in terms of elementary mathematical functions, so it is difficult to determine whether or not this formalism is consistent with the experimentally observed data. It is possible to deduce the systemic behavior of simple specific systems involving a few rational functions and find examples in which the elements do not exhibit allometric relationships. So, in... [Pg.125]

As a local representation, the S-system variant within the Power-Law Formalism is more accurate than the GMA variant, which is generally more accurate than the conventional Linear Formalism. As a fundamental representation, the Power-Law Formalism includes as special cases the Mass-Action, Michaelis-Menten, and Linear Formalisms that are considered to accurately represent natural phenomena... [Pg.137]

It was found that the ROP of compounds X-CF-Y by means of the transacetalation reaction (formal metathesis) carried out in CH2CI2 at 0°C in the presence of Et20-Bp3 as a catalyst is folly reversible, and produces the DLs of cyclic and linear formals described in Scheme 8. [Pg.23]

The linear formalism implies, that for many classes of problems in deformation, solutions in the viscoelastic case can be simply obtained from elastic solutions by Laplace transform methods as for isotropic materials. Further in particularly simple cases this reduces to simple replacement of constants in elastic solutions by their time dependent analogues in creep. Most of the work of determining significant creep parameters for oriented materials falls into this latter class. [Pg.330]

The Fixman theory was quite heuristic and bears little resemblance to later versions of mode-mode coupling. The theory was based on macroscopic hydrodynamic considerations of energy dissipation in a sound wave. The theory makes beautiful physical sense, but does not concern itself with the classical linear formalism that we have just discussed. Thus, the Fixman theory allows no determination of why our assumptions about K Xt) break down. Understanding of this point was achieved via the more formal theories of Kawasaki and of Kadanof and Swift. ... [Pg.267]

When the variable at the global level is a scalar, the sequence of operators previously established applies. The three localization levels and the operators linking them can be represented by a linear Formal Graph that merely adapts Graph 5.8 to the case of identical operators, as shown in Graph 5.9. [Pg.124]

The three localization levels and the operators linking them can be represented by a linear Formal Graph shown in Graph 5.10. [Pg.126]

Matzner, Noshay and McGrath have also reported the use of low molecular weight aromatic linear formals (based upon BPA and Tetramethyl BPA) to form organosiloxane block copol)nners. However, no details were provided on the synthesis of these low molecular weight formals. [Pg.69]

A variety of other new polymer systems have also been S3ni-thesized based on this chemistry. These include block copoly-formalcarbonates, polycarbonates using the linear formal dimer of BPA, and polyethersulfoneformals. [Pg.100]


See other pages where Linear formalism is mentioned: [Pg.466]    [Pg.466]    [Pg.500]    [Pg.466]    [Pg.100]    [Pg.70]    [Pg.90]    [Pg.97]   
See also in sourсe #XX -- [ Pg.51 , Pg.216 ]

See also in sourсe #XX -- [ Pg.125 , Pg.140 ]




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