Molecular elucidation

By focusing on a molecular elucidation of key biochemical processes in the marine biogeochemical cycles of elements, marine bioinorganic chemistry should help us understand the subtle and complex interdependence of marine life and ocean geochemistry, and how they have evolved together over the history of the Earth. 

Proteins are major components in dendritic nerve membranes and may exhibit electroactivity—i.e., the characteristic of being switched between two states of differing ionic conductivities. Such electro-activity is interesting because the electricity of the nerve impulse, the unitary basis of information encoding in neural systems, is generated in the dendritic membrane, which is composed of electro-chemically active proteins in a lipid bilayer. Thus, by interacting with neuroscientists in the investigation of neural information code(s), electrochemists may make fundamental contributions to the molecular elucidation of the human brain and the nervous systems of other major animal species (6). 

The concept of chemical speciation and speciation analysis is continuously evolving in such a way that the discovery and molecular elucidation of new (semi) metal-biomolecules are now possible via speciation analysis with hyphenated techniques. Of course, a discovered metal-biomolecule can be the signature of a new biochemical reaction mechanism paving... 

Despite the historical tendency of models to represent POA as a non-volatile mixture, there is longstanding and compelling evidence that POA emissions are substantially semi-volatile. The evidence comes in two major forms. First, both volatility-based chromatography and molecular elucidation of emissions profiles for various sources show clearly that most POA emissions span a wide range of C values and that most of those are 1 pg m [89, 90]. This is often simply a consequence of the properties of the parent materials for the emissions, such as lubricating oil. Second, when the gas-particle equilibrium is perturbed, either via isothermal dilution or via heating, POA particles shrink. 

SIMS measures the elemental, isotopic, and molecular distributions on and/or within a solid. Elemental and molecular elucidation is arrived at by essentially weighing each of the respective elemental/molecular secondary ions. A solid is composed of many atoms/ions and/or molecules, with the solid s properties, inclusive of density, defined by the bonding between the respective atoms. 

NMR is a valuable technique in molecular elucidation and verification. In some instances, the NMR spectrum is sufficient for identifying relatively simple unknown compounds while in other applications structural information from NMR spectra compliments that of other chemical and spectroscopic methods. FTNMR... 

Polyamine-Derived Alkaloids in Plants Molecular Elucidation of Biosynthesis... 

P. Sukitpaneenit and T.S. Chung, Molecular elucidation of morphology and mechanical properties of PVDF hollow fiber membranes from aspects of phase inversion, crystallization and rheology. Journal of Membrane Science 340 (2009) 192-205. 

Sukitpaneenit, P. and T.-S. Chung. 2009. Molecular Elucidation of Morphology and Mechanical Properties of PVDF Hollow Fiber Membranes from Aspects of Phase Inversion, Crystallization and Rheology. Journal of Membrane Science 340(1/2) 192-205. doi 10.1016/j.memsci.2009.05.029. 

Flowever, in order to deliver on its promise and maximize its impact on the broader field of chemistry, the methodology of reaction dynamics must be extended toward more complex reactions involving polyatomic molecules and radicals for which even the primary products may not be known. There certainly have been examples of this notably the crossed molecular beams work by Lee [59] on the reactions of O atoms with a series of hydrocarbons. In such cases the spectroscopy of the products is often too complicated to investigate using laser-based techniques, but the recent marriage of intense syncluotron radiation light sources with state-of-the-art scattering instruments holds considerable promise for the elucidation of the bimolecular and photodissociation dynamics of these more complex species. 

Trentler T J ef a/1997 Solution-liquid-solid growth of indium phosphide fibers from organometallic precursors elucidation of molecular and non-molecular components of the pathway J. Am. Chem. Soc. 119 2172... 

Similarity search appears as an extremely useful tool for computer-aided structure elucidation as well as for molecular design. Here the similarity property principle is involved. This may be stated as ... 

Similarity search appears as an extremely useful tool for computer-aided structure elucidation as well as molecular design. 

To identify the main methods and tools available for the computer prediction of spectra from the molecular structure, and for automatic structure elucidation from spectral data... 

Furthermore, the prediction of and NMR spectra is of great importance in systems for automatic structure elucidation. In many such systems, aU isomers with a given molecular formula are automatically produced by a structure generator, and are then ranked according to the similarity of the spectrum predicted for each isomer to the experimental spectrum. 

Jones G, P Willett and R C Glen 1995a. A Genetic Algorithm for Flexible Molecular Overlay an Pharmacophore Elucidation. Journal of Computer-Aided Molecular Design 9 532-549. 

The molecular ions yield molecular mass information and molecular formulae. These in themselves are very useful but are usually insufficient to fully elucidate the structure of an unknown substance. 

It is not the purpose of this book to discuss in detail the contributions of NMR spectroscopy to the determination of molecular structure. This is a specialized field in itself and a great deal has been written on the subject. In this section we shall consider only the application of NMR to the elucidation of stereoregularity in polymers. Numerous other applications of this powerful technique have also been made in polymer chemistry, including the study of positional and geometrical isomerism (Sec. 1.6), copolymers (Sec. 7.7), and helix-coil transitions (Sec. 1.11). We shall also make no attempt to compare the NMR spectra of various different polymers instead, we shall examine only the NMR spectra of different poly (methyl methacrylate) preparations to illustrate the capabilities of the method, using the first system that was investigated by this technique as the example. 

Analysis of Surface Molecular Composition. Information about the molecular composition of the surface or interface may also be of interest. A variety of methods for elucidating the nature of the molecules that exist on a surface or within an interface exist. Techniques based on vibrational spectroscopy of molecules are the most common and include the electron-based method of high resolution electron energy loss spectroscopy (hreels), and the optical methods of ftir and Raman spectroscopy. These tools are tremendously powerful methods of analysis because not only does a molecule possess vibrational modes which are signatures of that molecule, but the energies of molecular vibrations are extremely sensitive to the chemical environment in which a molecule is found. Thus, these methods direcdy provide information about the chemistry of the surface or interface through the vibrations of molecules contained on the surface or within the interface. 

---