Configurational arrangements

Konstanz, n. constancy, konstatieren, v.t. ascertain, establish, verify. Konstellation, /. constellation configuration, arrangement (as in microstructure), konstituieren, v.t. constitute. Konstitutions-formel, /. constitutional formula. 

Commercially available processes for resid HCK deal with catalyst life cycle issues by the use of different catalyst/reactor/configuration arrangements. In Ref. [142], Morel et al. discuss the performance and features of these arrangements. A summary of conditions for each reaction system is collected in Table 11. 

The variation in polymer structures is observed when the backone of the polymer molecule contains a carbon atom attached to two different side groups. Such polymers can have different configurational arrangements or tacticity. 

After they had successfully separated [2.2]paracyclophane-4-carboxylic acid 11a 41> into its antipodes by fractional recrystallization of the (-)-a-phenylethylamine salt from ethanol, Cram and Allinger 37> turned their attention to the relative configurational arrangements within individual members of this class of compounds and the type of relationship existing between optical properties and absolute configuration. 

Replacement of the conventional incoherent light source with a laser has allowed CD measurements to be made on extremely small samples, such as those encountered in capillary electrophoresis. In addition, the unique spatial properties of the laser are utilized to advantage in thermal lens spectroscopy. TL detection of CD, either via a single beam, or a differentially configured arrangement, has demonstrated significant improvements in the measurement SNR. Application to HPLC detection, or time-resolved studies, are currently under investigation. 

Table IV is a concise summary of the effect of the number of aromatic rings and their configurational arrangement on the hydrogenation kinetics of relevant polynuclear...

Table IV. Summary of the effect of the number and configurational arrangement of aromatic rings on the hydrogenation kinetics of aromatic model compounds (54)...

Microstates are the atomic states that result from interactions between electrons in a many electron system (mi and ms values). The microstate table lists all the possible microstates for a given electron configuration arranged according to the Ml and Ms values. In the case of a np2 configuration the microstate table will be of the form... 

Detector configuration arrangement of multiple detectors in series or in parallel can cause additional peak broadening, flow rate variations, back pressure variations,... 

It will therefore be characterized by an activation energy for the jump of a segment of a polymer chain from one equilibrium position to the next it also depends on the local configurational arrangement of nearest neighbor segments ... 

In the late 1960s, as part of an effort devoted to the preparation of high-order annulene polyoxides, J. A. Elix attempted a Wittig-type self-condensation of 5-formyl-2-furfurylphosphonium chloride 1.19 While the products that resulted were predominantly polymeric, small quantities of macrocyclic products were isolated. These latter consisted of trimers, tetramers, and pentamers (discussed in Chapters 2, 4, and 6, respectively), as well as a hexamer. Unfortunately, this hex-americ [36]annulene hexoxide product represented by structure 7.80, was only obtained in 0.05% yield (Scheme 7.7.1). Thus, Elix was unable to elucidate the exact configurational arrangement of the double bonds in this product. Still, as discussed below, this issue could be addressed at least in part, by spectroscopic means. 

As a corollary, N-monosubstituted and unsymmetrically /V-disubstituted derivatives are expected to exhibit (E)-(Z) geometrical isomerism. In the case of N,Nr-unsymmetrically disubstituted thioureas, up to four different configurational arrangements can be envisaged, the (E,E) isomer being generally absent because of steric repulsion between the nitrogen substituents (Fig. 3). 

Bismuth(III) acetate reacts with cyclohexene to produce 1,2-diacetatocyclohexane. If conditions exclude water, a trans configuration arrangement of the two acetate groups is obtained, while the configuration is cis if water is included in the reaction (equations 14 and 15). ... 

As an example for a one-dimensional property transfer, the preparation of optically active co-polymers using chiral template molecules is described. In this case, the optical activity in the polymer arises from the chirality of the configurational arrangement of the main chain (main chain chirality). Symmetry considerations show that there are several possible structures both for stereoregular homo- and for co-polymers in which this type of chirality can be expected [4]. 

Stereoisomers are compounds having the same number and kinds of atoms, the same configuration (arrangement) of bonds, but altogether different 3D-structures i.e., they specifically differ in the 3D-arrangements of atoms in space. 

Enantiomers are isomers whose 3D-configuration (arrangement) of atoms gives rise to the formation of nonsuperimposable mirror images. 

Configuration —Arrangement fixed by primary valence bonds can be altered only through the breaking or reforming of chemical bonds... 

For polymers prepared from monomers of the general structure CH2=CR R where R and R are two different substituent groups, there are two distinc configurational arrangements of the repeat unit ... 

Polymerization of olehns results in the variation of geometrical and configurational arrangements (named tacticity) [8]. Having control of these arrangements is an issue of particular importance because tacticity affects the physical properties of the polymer. 

The radiation dose from gas-turbine depends on its detail design configuration, arrangement, shieldings, etc. In this calculation, it is assumed that (a) FPs plateout on the inner surface of infinite tube, (b) an evaluation point is 1 m from the tube and (c) shielding material is 3 cm of iron. 

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