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The possibility of realizing fast and efficient near-infrared (NIR) light detectors is explored based on bulk heterojunction of a p-diphenoquinone analog extended by di-hydrobithiophenediylidene, a quinoid molecule featuring a high absorption band and poly[2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene]. Photoexcitation and relaxation dynamics in pristine materials and bulk heterojunction are examined by using pump-probe measurements, disclosing charge transfer from 5,5'-bis(3,5-di-tert-butyl-4-oxo-2,5-cyclohexadiene-1-ylidene)-5,5'-dihydro-2,2'-bithiophene (QBT) to polymer and efficient energy transfer the other way round.

The atomic relaxations in a model liquid are calculated by using the kinetic model for liquids, which have given a quantitative description of liquid substructures. The degree of cooperation in relaxation is determined by the number of atoms (N) in the liquid substructure and is responsible for the fragility of liquids, indicating that the larger the N is, the more fragile the liquid is.

Snoek relaxation behavior of a Ti-25.2Nb-0.6O at. % alloy is examined on three specimens with specific crystalline orientations along the flexure vibration stressing direction. The Snoek relaxation peak is modeled by a continuous spectrum and a dipole shape factor of 0.42 is obtained for the alloy with the average orientation parameters calculated by the optimized sampling grain approximation method.

A study is conducted to explore the phonon-induced electron relaxation in a lateral double quantum dot embedded in a suspended slab. The results showed that the relaxation rate strongly depends on the phonon character of the slab and could be enhanced by tuning the electric field, which could also be applied to manipulate the relaxation rate in lateral double quantum dots.

The growth strains and creep relaxation in [alpha]-[Al.sub.2][O.sub.3] films, isothermally grown on [beta]-NiAl alloys at 1100 [degree] centigrade, are measured. A balanced defect model has emerged that is consistent with the dynamic segregation model, observed growth stresses and their dependence on the presence of a reactive element, sequential oxidation experiments.

The polarization effects of localized charged carriers are studied by using quantum/classical quantum mechanical (QM) and molecular mechanical (MM) approaches with charge redistribution and polarizable force field schemes and are applied to the crystals of naphthalene through pentacene. The total relaxation energies for QM/MM models of the naphthalene crystal are examined to estimate the impact of intermolecular nuclear relaxation.

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.

The relaxation of vertical and horizontal force components in a high-temperature superconducting levitating system, with different initial cooling process after fixing the levitated body in an expected position statically, are studied. The studies have shown that when levitation height (LH) is fixed at the cooling height (CH), the transition phenomenon is observed in the levitation force behavior and their relaxation under different lateral displacements (LDs).

The strain relaxation mechanisms and the associated defect dynamics in ultrathin Cu films subjected to a broad range of biaxial tensile strains are analyzed. The studies have shown that due to the defect mechanisms, nanoscale domains are formed in the crystalline film with an average domain size and low-angle misorientations.

The evolution of Ge islands during postgrowth annealing for different durations at a representative temperature of 650 degree centigrade is described. The results have correlated the morphological transformation of islands with the composition and strain relaxation.

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.

A study was conducted to analyze the carrier/spin dynamics of two InAs samples grown on (001) and (111) GaAs by metal-organic chemical vapor deposition (MOCVD) technique. The observation for shorter spin relaxation time at higher fluence indicated that Elliot-Yafet (EY) mechanism dominates the spin relaxation process.

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.

The linear combination of atomic orbitals (LCAO) is applied on the analysis of propagating spin waves in two-dimensional (2D) and three-dimensional (3D) superlattices consisting of spherical ferromagnetic nanoparticles. The results have shown how the weak dipolar interaction has increased or decreased the relaxation time in the samples with a controlled direction of the easy axis.

An extended form of Volterra process, which is used to study the relaxation mechanisms that are associated with disclinations in any solid system, is discussed. The approach has also been used to detect dislocations and continuous defects in the complex structures with high plasticity.

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.

Bulk metallic glasses with critical diameter are described over a relatively wide composition range in the Mg-Cu-Ag-Gd quaternary system. The fragility parameters for the glass-forming liquids are obtained by analyzing the relaxation time based on the Vogel-Fulcher-Tamman (VFT) equation.

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 epitaxial growth of CaO films on mechanical-damage-free MgO(001) surface by using low-temperature buffer method is examined. The unique strain relaxation mechanism and interfacial dislocation configuration are found to be due to the dislocation kinetics that has driven the misfit dislocations slipping perpendicular to the interface.

The impact of chemical ordering on the dielectric properties of the thin film relaxor lead scandium tantalate (PST) is examined. The impact of the defects and the quantitative reduction of the area of true relaxor regions are responsible for low permittivity thin film relaxors, which possess similar features to ceramic relaxor behavior.

The magnetic relaxation effects in [Fe.sub.73.9][Nb.sub.3.1][Cu.sub.0.9][Si.sub.13.2][B.sub.8.9] amorphous thin films produced by ion beam sputtering are analyzed by using different methods as a function of magnetic anisotropy. Magnetization relaxation has occurred on time scales of tens of seconds and relaxation intensity is found to be higher when measured along the easy magnetization axis.

The electron-emission properties of relaxation-induced traps in InAs/GaAs quantum dots (QDs) are studied by using capacitance-voltage (C-V) profiling and bias-dependent deep-level transient spectroscopy. The relaxation-induced trap is identified to be the misfit trap located at the QD and at the observed emission energy below the GaAs conduction band.

Neutron reflectometry and isotope multilayers are used for examining self-diffusion in covalent amorphous solids during isothermal annealing and its correlation to structural relaxation. The decrease in nitrogen diffusivity is interpreted as a structural relaxation of the amorphous network structure that is governed by annihilation of interstitial-like defects.

The different spraying modes for ac spraying, transition between them, role played by different time scales in the beginning of these modes are presented. One of the results conclude that transition between different modes depend on the fraction of the charged relaxed in the liquid.

The parameters to optimize the measurement of longitudinal relaxation time detection is examined with the help of a high-[T.sub.c] superconductive quantum interference device magnetometer. Results reveal that the data are uniform with the derived longitudinal relaxation time of water measured from the increase of magnetization with the duration of the polarizing field.

The single-quantum [1.sup.H]-CPMG (Carr-Purcell-Meiboom-Gill) relaxation dispersion NMR spectroscopy for separating degenerate [1.sup.H] transitions in methyl group is presented. The sequence can also be well used for protein systems that do not undergo chemical exchange.

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 analysis presents a time-domain ab initio study of the electron dynamics, charge relaxation and recombination in the dye-sensitized [TiO.sub.2] molecule. The results prove that the back electron transfer (ET) taking place in the electrolyte is normally promoted by the various electrolyte vibrational modes present.

Molecular dynamics simulations are employed to analyze the [super 2]H relaxation data of a large number of compounds to estimate the methyl rotation barriers, as well as the corresponding activation energies of different proteins. The methyl rotation barriers are found to be quite high in most of the cases due to the tight packing of the side chains and hence can be easily used in the structural work of many proteins.

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 two magnon scattering theory is derived for microwave relaxation in magnetic systems in the framework of the Hamiltonian formalism. General expressions are provided for inhomogeneity coupling coefficients in the case of localized inhomogeneities and an approximate solution is presented for the relaxation rate of the ferromagnetic resonance uniform mode relaxation rate.

The photoinduced effect and the transport characteristics are investigated in the charge-ordering [La.sub.0.5][Ca.sub.0.5]Mn[O.sub.3] (LCMO) film, which is prepared by the radio frequency (rf) magnetron sputtering method. The photoinduced relaxation has shown different processes when the laser is on and off, which is attributed to thermal fluctuation, and the charge-ordering transition temperature is found to be 280 K.

Relaxation of compressed InP and InGaAs at different strains and temperatures was investigated. It was observed that InP and InGaAs layers relax in three possible regimes, low-mismatch, high-mismatch and medium-misfit, which depend on the strain state of the film.

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 mechanism of resolution and sensitivity enhancement at high fields in magic angle spinning (MAS) NMR of spin 1/2 nuclei in solids was studied. It was seen that for [super 15]N CP/MAS NMR experiments, both the spectral resolution and sensitivity, enhances at higher static field.

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 contact photoacoustic technique is used to study the explosive boiling and lift-off of a thin layer of micron-sized transparent water droplets from an absorbing Si substrate heated by a nanosecond KrF laser. The results have shown that acoustic pressure buildup, bubble dynamics and the subsequent lift-off of the thin water layer are interpreted as relaxation stages after near-spinodal explosive boiling of the superheated interfacial water.

Relaxation oscillations in an argon capacitive discharge connected to a peripheral grounded chamber through a slot with dielectric spacers are described. The oscillations observed form time varying optical emission of the main discharge chamber show a high frequency relaxation oscillation with absorbed power near that for peripheral breakdown and a low frequency oscillation at higher absorbed power.

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.

A novel method based on a ratiometric approach that consists of measuring the ratio between the transverse and the longitudinal paramagnetic contribution to the water protons relaxation rate (A [R.sub.2p]/[R.sub.1p] is presented. Larger [R.sub.2p]/[R.sub.1p] values could be obtained in the presence of larger molecular reorientational time and faster exchange rate of water molecule coordinated to the Gd(III) ion.

Rabi oscillations are studied in a modulation-doped symmetric double quantum well when the two lower subbands are driven by a strong ac electric field. The results have shown that Rabi oscillations and significant electron transfer in the upper subband can occur even in the presence of relaxation processes.