Structure compatibility

Figure 32. Structure compatible with the observed magic number corresponding to (H20)s(M)6H+. Taken with permission from Int. J. Mass Spectrom. Ion Proc. 1994, 131, 233-264.

The simplest intermediate of the nitrogen cation type is the nitronium ion, the active species in most aromatic nitration reactions. There is both cryoscopic and spectroscopic (Raman and infrared) evidence for its existence.802 On the other hand, it has a structure with quaternary rather than electron deficient nitrogen, a structure compatible with the centrosymmetric geometry demanded by the spectra. The Raman line at 1400 cm.-1 has been assigned to the totally symmetric vibration of the linear triatomic molecule. 

Note 1 Mesogeuic is an adjective that in the present document applies to molecular moieties that are structurally compatible with the formation of LC phases in the molecular system in which they exist. 

Note 4 The pendant groups in these polymers have structures compatible with liquid-crystal formation, that is, they are mesogenic but not intrinsically mesomorphic. See the examples given in Definitions 2.10 2.11.2.1. 

A molecule s structure plays a critical role in its biological activity. Part of the job of many biological molecules is to bind to another molecule—the target —and affect its function in various ways. Binding usually requires structural compatibility. This compatibility ensures specificity—the molecule binds only to its target. For instance,... 

As the system is subjected to ongoing, low-level mechanical agitation, the network structure is rearranged to a dispersion of more compact floes that display both a lower yield value and a lower apparent viscosity than the initial dispersion (curve 2). A certain amount of time is required for the dispersed units to acquire a size and structure compatible with the prevailing low level of agitation. This is why intermediate cases (not shown in Fig. 4.14a) are observed before the actual stationary-state condition is obtained. 

There are 560 structures compatible with these limitations. They are represented by the following diagrams ... 

One of the original theories to account for the formation of the enzyme-substrate complex is the "lock and key" theory. The main concept of this hypothesis is that there is a topographical, structural compatibility between an enzyme and a substrate which optimally favors the recognition of the substrate as shown in Figure 2.3. 

Tn orcTer to extend these conformational energy studies to the analysis of multi-stranded nucleic acid systems, it is necessary to devise a procedure to identify the arrangements of the polynucleotide backbone that can acconmodate double, triple, and higher order helix formation. As a first step to this end, a computational scheme is offered here to identify the double helical structures compatible with given base pairing schemes. 

IgE antigens combined with in vitro tests of cross-reactions of IgE and sequenced antigens, as it has been found that the basic condition for positive cross-reactivity is the high structural compatibility (homology) of reagents. Compared to B-cells, T-cell cross-reactivity is far more difficult to assess because the mechanism of T-cell effects is more diverse and involves both the phase of immunological response and the effect phase of the allergic reaction. 

Lysine also may form complexes with anionic ligands and thereby increase Am values. In addition, lysine may have an unfavorable effect on protein structure. Because it has a considerable hydrophobic moment, it may interact with hydrophobic sites on the protein, leading to perturbation of structure. Compatible solutes lack a propensity for interacting with peptide backbone linkages or amino acid side-chains, as discussed later. 

In addition to joining, adhesives in electrical applications may be required to conduct heat, conduct or isolate electricity, provide shock mounting, seal, protect substrates, etc. Thermal and chemical resistance, weathering, and structural compatibility must also be considered in diverse electrical and electronic applications. Of course, the choice of adhesive will also be governed by application methods, cure temperature, processing speed, and overall economic cost. 

Fig. 83. Qualitative features of f.c. tet. (c/a > 1) indium. Tetragonal (c/a > 1) symmetry is a two-sublattice structure compatible with ordering of outer electrons into bonding s and pxpy bands. 

The elucidation of the primary structure of small organic molecules by tracing their carbon skeletons was, traditionally, the main focus of INADEQUATE experiments. It is not the first NMR experiment to be considered for such a task typically a standard set of NMR spectra, that is COSY, TOCSY, NOESY, HSQC and HMBC, are performed and analysed first. If ambiguities remain after inspection of standard spectra, the tracing of carbon-carbon connectivities is embarked on. Nevertheless, an example is presented below where carbon-carbon connectivities are included at an earlier stage in order to reduce the number of computer-generated structures compatible with the experimental data. 

Identification of all the molecular structures compatible with (r,R,t), that is construction of a set (]j> of all distinct equivalence classes of <7(R, t)>. Two molecular graphs belong to the same equivalence class Qj if and only if they are homeomorphic [27,28]. The set Qj is finite, provided that the system under consideration consists of a finite number of particles (nuclei and electrons). 

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