Main Conclusions

Dynamic mechanical measurements describe both the liquid and solid states and are the best methods for following the physical changes occurring during the polymerization in the whole conversion range. The main observations are 

Dielectric measurements are also able to monitor the polymerization from the initial liquid state to the final solid state (full cure). The main observations are 

Nevertheless, with the development of new sensors, microdielectrometry constitutes a nondestructive and convenient method for monitoring in situ and in real time the cure of thermosets (Senturia et al., 1982 Kranbuehl et al., 1986). Great efforts have been made and research is still going on to establish relationships between (i) cure index and actual conversion of reactive groups, (ii) conductivity and viscosity, and iii) conductivity and glass transition temperature, in order to obtain models for smart processing. 

A = u/(s + u) = ratio between scaling exponents y = scaling exponent for M Cx) 

De Gennes PG, Scaling Concepts in Polymer Physics, Cornell University Press, Ithaca, New York, 1979. 

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The results of the estimation of the distortion criterion s are presented in fig. 4. It is seen that the distortion increases with the noise. But the main conclusion is that the Gibbs functional (12) provides a satisfactory reconstruction having quite large noise up to 0.15, what can not be provided by other known reconstruction techniques. 

More accurately, as the inverse problem process computes a quadratic error with every point of a local area around a flaw, we shall limit the sensor surface so that the quadratic error induced by the integration lets us separate two close flaws and remains negligible in comparison with other noises or errors. An inevitable noise is the electronic noise due to the coil resistance, that we can estimate from geometrical and physical properties of the sensor. Here are the main conclusions ... 

We have previously calculated conformational free energy differences for a well-suited model system, the catalytic subunit of cAMP-dependent protein kinase (cAPK), which is the best characterized member of the protein kinase family. It has been crystallized in three different conformations and our main focus was on how ligand binding shifts the equilibrium among these ([Helms and McCammon 1997]). As an example using state-of-the-art computational techniques, we summarize the main conclusions of this study and discuss a variety of methods that may be used to extend this study into the dynamic regime of protein domain motion. 

The main conclusion we wish to draw from this line of development is that the difference between Ej and E could vary widely, depending on the nature o the active center. 

The main conclusion to be drawn from these studies is that for most practical purposes the linear rate model provides an adequate approximation and the use of the more cumbersome and computationally time consuming diffusing models is generally not necessary. The Glueckauf approximation provides the required estimate of the effective mass transfer coefficient for a diffusion controlled system. More detailed analysis shows that when more than one mass transfer resistance is significant the overall rate coefficient may be estimated simply from the sum of the resistances (7) ... 

Kinetics. Details of the kinetics of polymerization of THF have been reviewed (6,148). There are five main conclusions. (/) Macroions are the principal propagating species in all systems. (2) With stable complex anions, such as PF , SbF , and AsF , the polymerization is living under normal polymerization conditions. When initia tion is fast, kinetics of polymerizations in bulk can be closely approximated by equation 2, where/ is the specific rate constant of propagation /is time [I q is the initiator concentration at t = 0 and [M q, [M and [M are the monomer concentrations at t = 0, at equiHbrium, and at time /, respectively. 

After the publication of a book on the prototropic tautomerism of aromatic heterocycles (76AHC(Sl)l) which covered the literature up to 1975, the study of the tautomerism of pyrazoles has not made great strides. In this section the main conclusions of this earlier review will be summarized and comments on a few recent and significant references added. 

The main conclusion of an expert workshop on endocrine modulators and wildlife in 1997 was that some existing test methods, as defined in guidelines published by the Organization for Economic Cooperation and Development (OECD), could be adapted to incorporate specific endocrine disrupting endpoints, but that there might also be the need to develop new tests, e.g. for fish. On behalf of the UK Government, the MRC Institute for Environment and Health (lEH)... 

Flow distribution in a packed bed received attention after Schwartz and Smith (1953) published their paper on the subject. Their main conclusion was that the velocity profile for gases flowing through a packed bed is not flat, but has a maximum value approximately one pellet diameter from the pipe wall. This maximum velocity can be 100 % higher than the velocity at the center. To even out the velocity profile to less than 20 % deviation, more than 30 particles must fit across the pipe diameter. 

More recently, in the middle 1990s, the UK s Health and Safety Executive (HSE) also reviewed the push-pull system. Hollis and Fletcher offer a comprehensive literature review on push-pull ventilation and note that the main conclusions of previous work on push-pull ventilation of tanks are that the control is primarily supplied by the inlet jet, forming a wall jet along the surface of the tank, and that the main purpose of the exhaust hood is to remove the air and contaminant contained within the push jet. 

The main conclusions from the work on water injection describes in this chapter are as... 

The main conclusion which can be drawn from the results presented above is that dimerization of particles in a Lennard-Jones fluid leads to a stronger depletion of the proflles close to the wall, compared to a nonassociating fluid. On the basis of the calculations performed so far, it is difficult to conclude whether the second-order theory provides a correct description of the drying transition. An unequivocal solution of this problem would require massive calculations, including computer simulations. Also, it would be necessary to obtain an accurate equation of state for the bulk fluid. These problems are the subject of our studies at present. 

Flow fields resulting from these combustion modes were computed by means of similarity methods (Section 4.2.1) and used to provide initial conditions for numerical computations. The main conclusion was that blast waves at some distance from the charge were very similar, regardless of whether the combustion mode was detonation or strong deflagration. 

The main conclusion on the influence of substituents in the imidazole ring on the state of the tautomeric equilibria 14a 14b is that electron-withdrawing groups favor the 4-position, i.e., the tautomers 14a with = Hal, NO2, and so on, are the energetically preferable species. Application of Charton s equation, Kt = [4-R Im]/[5-R Im] = 3.2 was discussed in detail [76AHC(S1) 96CHEC-II(3)77]. The equation was found to be in a qualitative agreement with the experimental data presented in Table III. 

A common feature of the three PTEB samples is that the yield stress decreases as the drawing temperature increases (Table 2), whereas it does not change significantly with the strain rate. The Young modulus does not change with the strain rate but it decreases and the break strain increases as the drawing temperature increases. The main conclusion is that the behavior of PTEB-RT is intermediate between the other two samples, with the advantage of a considerable increase in the modulus in relation to sample PTEB-Q and without much decrease in the break strain (Table 2). 

We note dial highly correlated calculations performed on isolated slilbene indicate that the first excited stale strongly optically coupled lo die ground stale is mil (he lowest in energy, in contrast to the INDO/SCI results [44 however, emission lakes place from the strongly coupled excited stale when relaxation effects are considered thus, the exact ordering of the lowest two excited stales in slilbene does not modify the main conclusions of our study. 

The main conclusions from this study are that the electron-drawing fluorine substituent produces a decrease in the association constant by a factor of about 3 for PC-based solutions and of 5.5 for solutions in DME [81] (cf. also Fig. 5). The consequence is an increase in the maximum of conductivity by about 30 percent (PC) and about 80 percent (DME). 

As a first example of applying the techniques described in section 2 let us look at the chain motion of linear polyethylene (LPE). A detailed study of a perdeuterated sample, isothermally crystallized from the melt, has been carried out in our laboratory24,25,44). Since all of this work is published and, in fact, has been reviewed extensively17 we can restrict ourselves to stating the main conclusions here ... 

Drops in electric potential between dissimilar phases are not experimentally measurable.29 This aspect was discussed at length in the literature between the early 1970s and 1990. The discussion was about what is actually measured as electrode potentials are measured. Now a general consensus seems to have been achieved. While readers are referred to the original literature,3 5 1517 29"31 the main conclusions are summarized here. 

A study of the eeo-efficiency of the recovery of packaging waste was eommissioned by APME and undertaken by the Duteh seientifie research institute, the TNO. This article provides information on this study, under sections entitled model for the study, waste scenarios, environmental and economic impact, eeo-efficiency of waste management, and finally, main conclusions. 

A new study carried out by Dow Europe and published by APME indicates that both mechanical recycling and energy recovery have a vital role in ensuring the most environmentally efficient disposal for plastic bottles. The survey carried out by Dow uses the example of an HD PE bottle. Main conclusions of the report are indicated. 

Even though the predicted relative instability of BF would be somewhat diminished by such an extension of the basis, the main conclusion remains the Oqq molecule is still about 530 kcal/mol higher in energy than a corresponding fragment of bulk graphite. 

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