Aims of investigation

Polydiacetylenes are polymers showing a one-dimensional semiconducting behaviour. This one-dimensional structure causes exceptionally high third order non-linearities [100], also in off-resonant wavelength regions [101], with extremely short sub-picosecond switching times [102]. After this discovery it was believed that an optical amplifying switch (optical transistor) or even an optical computer was close at hand. 

In this scenario, polydiacetylenes were nevertheless interesting, as the mechanisms of their large non-linearity form a good basis to build on. Only a few modifications were well characterised and there was a general lack of measurements with single crystals due to problems with sample preparation. Therefore, the aim was to characterise systematically the influence of side groups on the optical properties, preferably in the macroscopically ordered, stable, and reproducible framework of good and - later on - thin crystals. 

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This chapter compares the reaction of gas-phase methylation of phenol with methanol in basic and in acid catalysis, with the aim of investigating how the transformations occurring on methanol affect the catalytic performance and the reaction mechanism. It is proposed that with the basic catalyst, Mg/Fe/0, the tme alkylating agent is formaldehyde, obtained by dehydrogenation of methanol. Formaldehyde reacts with phenol to yield salicyl alcohol, which rapidly dehydrogenates to salicyladehyde. The latter was isolated in tests made by feeding directly a formalin/phenol aqueous solution. Salicylaldehyde then transforms to o-cresol, the main product of the basic-catalyzed methylation of phenol, likely by means of an intramolecular H-transfer with formaldehyde. With an acid catalyst, H-mordenite, the main products were anisole and cresols moreover, methanol was transformed to alkylaromatics. 

Anodic oxidation in inert solvents is the most widespread method of cation-radical preparation, with the aim of investigating their stability and electron structure. However, saturated hydrocarbons cannot be oxidized in an accessible potential region. There is one exception for molecules with the weakened C—H bond, but this does not pertain to the cation-radical problem. Anodic oxidation of unsaturated hydrocarbons proceeds more easily. As usual, this oxidation is assumed to be a process including one-electron detachment from the n system with the cation-radical formation. This is the very first step of this oxidation. Certainly, the cation-radical formed is not inevitably stable. Under anodic reaction conditions, it can expel the second electron and give rise to a dication or lose a proton and form a neutral (free) radical. The latter can be either stable or complete its life at the expense of dimerization, fragmentation, etc. Nevertheless, electrochemical oxidation of aromatic hydrocarbons leads to cation-radicals, the nature of which is reliably established (Mann and Barnes 1970 Chapter 3). 

Similar equipment for applications on the laboratory scale has been reported (and has recently been commercialized) (69-72). Most of the reported applications had the aim of investigating kinetics of chemical reactions as indicated by changes in liquid-phase concentrations. The equipment can typically be used at elevated temperatures and pressures. Applications to heterogeneous catalytic reactions include investigations of the enantioselective hydrogenation of exocyclic a,p-unsaturated ketones catalyzed by Pd/C in the presence of (A)-proline (73) and the esterification of hexanoic acid with octanol catalyzed by a solid acid (the resin Nafion on silica) (74). 

This is the standard dispersion model for P, and the aim of investigating more complex situations has often been to reduce them to this form with D = De, an effective dispersion coefficient that wraps up the complexities of the underlying situation in a single quantity. Whether this is wise is another matter. For example, in a packed bed the flow is obviously very complex, but both theory [4] and experiment can be invoked to justify an effective Peclet number, URIDe, of about 2. The question that hangs over the use of Eq. (33) is that it is a parabolic equation, with infinite signal speed and controversial boundary conditions. 

Anodic oxidation in inert solvents is the most widespread method for cation radical preparation, with the aim of investigating their stability and electron structure. However, saturated hydrocarbons cannot be oxidized in an accessible potential region. There is one exception for molecules with the weakened C—H bond, but this does not pertain to the cation radical problem. 

General analysis. The aim of investigations here is to establish a relation between the type of reaction behaviour (dynamic and steady-state)... 

Professor Nikolai M. Emanuel paid great attention to creation of development of novel methods of chemical physics. One of such methods is EPR-spectroscopy. In Department directed by Nikolai Emanuel the method of EPR-spectroscopy of spin marks and probes, in particular with the aim of investigation of polymer and polymer systems was actively developed. 

Therefore further experiments with a 250 kW Fan Conveyor Fed Furnace have been carried out with the aim of investigating the possibilities of NOx reduction by combustion air controlling. The investigations have been carried out with chipboard chips, chipboard sawdust, and spruce wood chips as fuel. 

The Interventional Management of Stroke (IMS I) Study was a multicenter, open-label, single-arm pilot study with the aim of investigating the feasibiUty and safety of a combined IV and lA approach to recanaUza-tion in patients with ischemic stroke. A total of 80... 

In a work by Chen et al. [186], Brownian dynamics was used to simulate the formatimi of micelles constituted of PS-PEO in water, with the particular aim of investigating the processes involved in flash nanoprecipitation . The effective (coarse-grained) potential was carefully mapped to experimentally determined... 

One of the main aims of investigating electric field effects on chemical transformations is to determine the reaction mechanism and, in simple cases, the dipole moments of the reaction partners. As outlined above, the rate constants provide the key information. 

So with the aim of investigating the reversal of charge concentrations of cations in gelatin and casein pH values of about 9.7 were chosen. Such high pH values... 

The main aim of investigations on this insert was to obtain the SVER value for the core of real design and mixed power-grade plutonium fuel. Experiments conducted before were carried out with weapon-grade plutonium in a tube-and-peUets structure of the BFS. 

Specific aim of investigation performed was to improve the existing design of BN-800 (variant 1) to facilitate decommissioning. Four optimization criteria were involved the total activity of used reactor materials (without fuel subassemblies), the total radwaste quantity, the cost of safe waste management, re-use and final disposal. 

The results of typical tests of the comprehensive laboratory experimental program carried out on the BLADE shaking table are discussed hereafter, with the aim of investigating some particular aspects of seismic SPSI. 

The evaluation of the level of adherence to the MeD in an Itahan Mediterranean region was also evaluated through the Moli-sani Project conducted at the Catholic University of Campobasso. The Moli-sani Project is a prospective, population-based cohort study that in the period 2005—2010 recruited 25,000 citizens from the southern Itahan region of Molise with the aim of investigating the importance of genehc—environment interactions to the onset of cardiovascular and tumor diseases, the two major killers affecting Western sodeties. ... 

The first example published in the literature concerning the use of the hexameric capsule in catalysis was actually an example of catalytic modulation through encapsulation. Scarso and coworkers selected the very well known photocatalyst [Ru(bpy)3] (bpy, 2,2 -fetT-pyridine) that, thanks to its pseudospherical shape and its cationic character, perfectly fits the cavity of the capsule with the aim of investigating the effect of reversible binding on the photocatalytic activity of the metal catalyst [25]. 

Transient response method (TRM) experiments were then performed with the aim of investigating the dynamic response of the system to step changes of the reacting mixture composition. Figure 10.4 (a, b, and c symbols) show some TRM runs carried out at different T. 

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