Local structuring mechanism

We find that the nucleation proceeds via "the local structuring mechanism/ " i.e., a thermal fluctuation causing the local ordering of CO2 molecules leads to the nucleation of the clathrate, and not by the labile cluster hypothesis, one current conceptual picture. The local ordering of the guest molecules induces ordering of the host molecules at the nearest- and next-to-nearest-neighbor shells, which are captured by a three-body host-host order parameter, f these thermodynamic fluctuations lead to the formation of the critical nucleus. 

Epoxides are found in thousands of biological molecules and constitute vital functional entities. They can impart localized structural rigidity, confer cytotoxicity through their role as alkylating agents, or act as reactive intermediates in complex synthetic sequences. The widespread occurrence of epoxides is contrasted by only a handful of aziridines that are known to date. In this chapter we would like to introduce the different mechanisms by which enzymes produce epoxides. 

A refinement of previous hypotheses concerning the local structure of turbulence in viscous incompressible fluid for high Reynolds numbers. Journal of Fluid Mechanics 13, 82-85. 

X-ray absorption spectroscopy can provide information concerning oxidation state and local structure of metals deposited on FGG catalysts and related supports, even at the several hundred ppm level. This information is valuable towards the understanding of catalyst deactivation and passivation mechanisms, and ultimately will lead to the development of new passivation routes. 

The growth of thin films on solid surfaces is important in technology, and nucleation is one of the keys for understanding the growth mechanism. The ability of STM to image local structures down to atomic detail makes it ideal for the study of nucleation, thin film growth, and crystal growth. 

Local anaesthetics JP Howe andJPH Fee Introduction Chemical structure Mechanism of action Pharmacokinetics Metabolism Toxicity... 

Getting Physical with Your Chemistry Mechanically Investigating Local Structure and Properties of Surfaces with the Atomic Force Microscope 76... 

The conversion of methanol to hydrocarbons (MTHC) on acidic zeolites is of industrial interest for the production of gasoline or light olefins (see also Section X). Upon adsorption and conversion of methanol on calcined zeolites in the H-form, various adsorbate complexes are formed on the catalyst surface. Identification of these surface complexes significantly improves the understanding of the reaction mechanism. As demonstrated in Table 3, methanol, dimethyl ether (DME), and methoxy groups influence in a characteristic manner the quadrupole parameters of the framework Al atoms in the local structure of bridging OH groups. NMR spectroscopy of these framework atoms under reaction conditions, therefore, helps to identify the nature of surface complexes formed. 

The computations described briefly in this paper illustrate the interrelationship between the local structure and macroscopic behavior of the DNA helix. Statistical mechanical studies help to identify the most likely morphological arrangements of the polynucleotide backbone and to understand the macroscopic flexibility of the DNA as a whole. Model building and potential energy calculations uncover the detailed local geometries of the chain and clarify the likely pathways between the multitude of allowed spatial forms. 

Attempts have been made to identify primitive motions from measurements of mechanical and dielectric relaxation (89) and to model the short time end of the relaxation spectrum (90). Methods have been developed recently for calculating the complete dynamical behavior of chains with idealized local structure (91,92). An apparent internal chain viscosity has been observed at high frequencies in dilute polymer solutions which is proportional to solvent viscosity (93) and which presumably appears when the external driving frequency is comparable to the frequency of the primitive rotations (94,95). The beginnings of an analysis of dynamics in the rotational isomeric model have been made (96). However, no general solution applicable for all frequency ranges has been found for chains with realistic local structure. 

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