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A methodology used to determine unrelaxed mobilities [mu]m of model peptides and proteins including finite bead size effects is outlined and the method used to account icon relaxation is examined. It is learnt that the effects of ion relaxation can be significant if the absolute electrophoretic mobility of a peptide exceeds approximately 0.20 [cm.sup.2]/ (kV s).

The water [2.super.H] and [17.super.O] magnetic relaxation dispersion (MRD) profiles from gelatin gels over wide ranges of resonance frequency and pH are reported. The MRD analysis shows a highly mobile hydration layer at the surface of the gelatin triple helix and a small number of trapped water molecules with residence times on the order of [10.sup.-8]s, presumably associated with structural defects and branch points in the gel.

The excitation relaxation dynamics of dimethylanthracene (DMA) in aqueous solutions in the presence of [alpha]-, [beta]-, and [gamma]-CDs was studied and it was found that there are both hydrated and anhydrated species of DMA in the [alpha]- and [gamma]-CD nanocavities. The structure of anhydrated (DMA)2-([gamma]-CD)2 is configured from the [(sup.1).B.sub.b] exciton splitting observed in the fluorescence excitation spectrum with the help of LJ + Coulombic potential calculations.

The dynamic disorder in the crystalline phases of anhydrous caffeine is studied using the dielectric technique of thermally stimulated depolarization currents (TSDC). The experimental results suggest that both crystalline phases II and I of caffeine, that have distinct crystal structures, are solid rotator phases showing reorientational glass transition at the same temperature in phase II and in metastable phase I.

The high-bias electrical properties of suspended metallic single-walled carbon nanotubes (SWNTs) are investigated at various temperatures in vacuum, in various gases, and when coated with molecular solids. The results reveal that the gas molecules surrounding suspended SWNTs assist the relaxation of hot phonons and afford enhanced current flow along nanotubes.

Electron spin lattice relaxation rates (1/T1e) of nitroxyl radicals were measured by saturation recovery at X-band, S-band and L-band. Further studies are required to understand the relevant motions of nitroxyls with different structures.

Supercritical CO2 is expected to be an environmentally benign media for reaction processes. The experimental determination or reorientational correlation provides a picture of solvation dynamics of CO2.

The triethylamine (TEA)/water system that provides a classic base model for phase separation in a relatively simple mixture is studied. This mixture has a lower critical consolute temperature and is also convenient for inducing phase-separation.

Low frequency dielectric study of glass-forming maltitol and sorbitol is performed. Side branching leads in maltitol to a sharpening of the corresponding distribution and occurrence of an intermediate strongly activated process, which has no separate secondary counterpart.

Vibrational relaxation, mode coupling, and peptide structural constraints are obtained by femtosecond two-dimensional vibrational spectroscopy of an acetylproline-NH2 model peptide. Three high-frequency vibrational modes are examined, two amide-I modes and the amide-II amino end mode, where efficient vibrational energy transfer between amide-I and amide-II bands located on the same amide are observed.

Transient absorbance pump-probe spectroscopy is used in studying the photoinduced electron transfer reactions in a porphyrin-viologen complex. Results indicate relaxation from the S2 to the S1 state in the wavelength region from 430 nm to 650 nm. Electron transfer occurs directly from the S2 state since the ZnTPPS(super 4-) to MV(super 2+) electron transfer could be time resolved. The back electron transfer took place with a lifetime of 0.8 plus/minus 0.1 ps.

The dynamics of micellization on a dodecylpyridinium iodide/water system has been studied through photon correlation measurements. It has been noted that large micelles are formed after the temperature goes down to 25 degrees C from 80 degrees C. The micellar radius exhibits extremely long relaxation times which may take several hours. The unfavorable equilibrium concentration of intermediates of submicellar size prevents the nucleation of micelle aggregates. This results in a nonequilibrium distribution with an excess of large micelles during thermal equilibrium.

Infrared spectroscopy was used to study the relaxation kinetics of two naturally occurring [alpha]-helices, L9:41-74 and L9:48-64 from the bacterium Bacillus stearothermophilus, in response to a laser-induced T-jump. The seven times slower folding rate of L9:41-74 compared to that of alanine-based peptides suggested that the folding time of [alpha]-helices in proteins is strongly dependent on sequence and chain length.

A time-resolved fluorescence method is used for studying the hydrogen-bonded network formed between 6-hydroxyquinoline (6-HQ) and acetic acid (AcOH). The unbridged complex has undergone excited-state proton transfer, but the Stokes shift is shown to be rather smaller.

Glass-forming liquids and polymers are analyzed to determine the association between nonexponentiality, [beta], and relaxation time, [tau]. The common relationship between the two quantities, [beta] and [tau], is influenced by the liquid elasticity length.

The role of temperature and membrane thickness on water absorption and desorption rates in Nafion membranes is presented. It is showed that interfacial transport and polymer relaxation dynamics control water absorption and desorption for thin Nafion films.

The studies of the spin-spin water relaxations in dilute aqueous solutions of [alpha], [beta], and [gamma]-cyclodextrins (CD), chemically modified [beta]-CD, and other carbohydrates are reported. The lower relaxation rate of water in CD solution is attributed to the intramolecular hydrogen bonding formed between the secondary hydroxyl groups that line the rim of the CDs.

The studies of the relaxation dynamics of unsubstituted porphyrin ([H.sub.2]P), diprotonated porphyrin ([H.sub.4][P.sup.2+]), and tetraoxaporphyrin dication (TOx[P.sup.2+]) is described. The results provide better understanding of the relaxation dynamics from the lowest [pi][pi]* states of monomer porphyrins for both free bases and metal complexes.

Infrared-visible sum-frequency generation (SFG) is used for analyzing the surface structure relaxations caused by temperature changes at the free surface of poly(methyl methacrylate). The studies have shown that the surface relaxation temperature is independent of film thickness for a free-surface phenomenon.

Laser photodissociation spectroscopy is used for measuring the visible spectra of phenylacetylene+ and 4-fluorostyrene+. The electronic relaxation is rationalized in terms of an apparent energy gap law for the benzene derivative cations.

The effect of oxygen in the EPR spectral properties of wood charcoals is measured and a model based on the properties of charcoals and EPR relaxation mechanisms is developed. EPR line broadening in these materials has correlated with char surface area and the concentration of adsorbed oxygen.

The relaxation times are evaluated for an electrolytic cell subject to a step-like external voltage, where the mobility of negative ions is different from that of positive ions. The relaxation processes connected with the ambipolar and free diffusion phenomena have described the dynamics of the system, when the diffusion coefficients are of the same order of magnitude.

The study explains the nucleation and the formation of the various collapses Langmuir monolayers obtained from semifluorinated alkanes.

The effects of triterpene glycoside (glycyrrhizic acid, GA) on the phototransformation of alkaloid lappaconitine (LA) are examined. It is shown that GA highly changes the efficiency, as well as the direction of such transformation by suppressing the process of deacylation.

The evidence for the existence of Johari-Goldstein secondary relaxation of water identified by the [nu]-process which could be useful to understand the glass transition of bulk water and dynamics of water/protein mixtures is presented.

The incident shock wave with the laser-schlieren technique was used to examine the dissociation and relaxation of C[O.sub.2]. The relaxation times are in agreement with available theoretical computations and incubation time to relaxation time ratio is found to be between 1.5 and 3 over 4000-6600 K.

A study is conducted to determine the relaxation behavior in the supercooled melt, using only viscosity data at temperatures above critical temperature based on the random walk (RW) approach. It was observed that the RW evaluated factors can be related with system features and are dependent on water content or sucrose concentration dependable regression results.

The role played by the carbonyl group in the antenna system of a naturally occurring photochromic chromene, flindersine (FL), and a structurally related unreactive heterocyclic compound, 6(5H)-phenanthridinone is investigated and compared. Result shows that the case of strong coupling conditions between closely spaced excited states, contributes to radiationless decay by transitions in which the upper of the two coupled states acts as an intermediate.

A variational principle for solutions to the Boltzmann equation is derived, which allows to extend the standard relaxation time approximation (RTA) using relaxation times that depend on the initial distribution. Tests of the approach on a calculation of the mobility for a one-dimensional (ID) tight-binding band indicate that analysis typically provides a better approximation than the standard RTA.

The vibrational coupling in the ground and excited states of positively charged naphthalene, anthracene, tetracene, and pentacene molecules is studied on the basis of a joint experimental and theoretical study of ionization spectra using high-resolution gas-phase photoelectron spectroscopy and first-principles correlated quantum-mechanical calculation. Findings show that while main contribution to relaxation energy in the ground state of oligoacene systems comes from high-energy vibrations, the excited-state relaxation energies show a significant redistribution toward lower-frequency vibrations.

The formation and mobility of Li point defects in Li2B4O7 are investigated theoretically with periodic quantum chemical calculations. It is seen that [Li.sup.+] ion migrates through a one-dimensional channel formed by the five-vertex lithium-oxygen (LiO5) polyhedra and local relaxation has a much larger impact on the calculated activation energy for Li migration than for the formation of the Li vacancy defect itself.

The linearized semiclassical (LSC) method is applied for calculating vibrational energy relaxation (VER) rates in the prototypical case of a rigid, symmetrical and linear triatomic molecule in a monoatomic liquid. It is found that the type and extent of the quantum rate enhancement is strongly dependent on the particular VER pathway and that the classical and semiclassical treatments can give rise to opposite trends when it comes to the dependences of the VER rates on the solvent.

Photoreactions in the gas-phase complexes [Mg.sup..+] (1,4-dioxane) and [Mg.sup..+] (1,3-dioxane) are examined in the wavelength region of 230-440nm. The main energy relaxation channel for both photoexcited complexes is the evaporation of [Mg.sup..+] and for photoreactions, the C-O bond is found to be much more prone to rupture than the C-C bond due to the coordination of O to [Mg.sup.+] in the parent complexes.

The collisional removal of vibrationally excited OH(v=1) by N((super 4)S) atoms is examined. The results have shown that the collisional removal of OH(v=1) by N((super 4)S) atoms is faster than that of OH(v=0).

Transient IR probing of energy gain in C[O.sub.2] is used to investigate the collisional relaxation of highly vibrationally excited 3- and 4-picoline with C[O.sub.2]. The statistical nature of collisional quenching in highly excited molecules is highlighted, even when there is clear evidence that the relaxation occurs via impulsive collisions.

The removal of both [C.sub.2]([X.sup.1]) and [C.sub.2]([a.sup.3]) by [O.sub.2] and NO in the temperature range from 300 to 24 K is reported in a low-temperature gas-phase kinetics study. It is found that the expected decoupling of the [C.sub.2]([X.sup.1]) and [C.sub.2]([a.sup.3]) system occurs, the triplet state is efficiently removed by [O.sub.2] in the temperature range 50-200K and the rate coefficient is essentially constant in the temperature range 36-300K.

The relaxation phenomena in a polymer/liquid crystal system, in its homogenous isotropic phase near the isotropic-isotropic, isotropic-nematic, and isotropic-smectic coexistence curve, using both polarized and depolarized photon correlation spectroscopy was investigated. The system was studied for different polystyrene molecular weights, different compositions, and different temperatures close to phase boundaries.

A computational study of the heme relaxation process in two tailored myoglobins-the His93Gly mutant with native heme b (b is in italic) and wild type myoglobins in which the two isopropionate side chains in the heme were each replaced by hydrogen atoms is presented. The simulation results suggest that little change in the relaxation rate is expected for the His93Gly mutant with native heme b (b is in italic) - and its acidic chains are intact.

Electrochemically generated films of poly (1-methylpyrroole), polythiophene, poly (3-methlythiophene), polyaniline and polymethylaniline are studied by potential steps in lithium perchlorate/acetonitrile solutions following the hypothesis of electrochemically stimulated confirmational relaxations model (ESCRM). The results states that the comparative treatment of different polymers by ESCRM allows to establish quantitative structural and thermodynamic magnitudes related to electrochemical processes.

The study is done of intramolecular dynamics taking place in a vibrationally excited isolated molecule under collision-free conditions and whose relaxation laws are expressed in terms of reduced time variables (Lau). It is concluded that phase space is explored according to essentially different relaxation laws in the regular and chaotic limits.

The interrelationship between J-coherence and the Keilson - Storer models of orientational relaxation is established. The validity of the Langevin description in reproducing the real time measurements of the anisotropy decay is discussed.