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The time-of-flight secondary ion mass spectrometry and reflection absorption infrared spectroscopy were used to determine the properties of supercooled liquid water and the mechanism of crystallization. The supercooled water is found to contain two phases and undergoes immediate crystallization and dissolution of LiCl.

A new route is described for rapid decrystallization of cellulose without esterification or morphology change on the macrofiber in trifluoroacetic acid (TFA). The esterification of TFA monomers on the external surface of crystalline cellulose, agglomeration of cellulose macrofibrils as well as water released from the esterification reaction has prevented the diffusion rate of TFA into the cellulose crystalline region and decreased the TFA swelling capability at higher temperatures.

The transition path sampling molecular dynamics simulations are used to investigate the crystallization of sodium chloride from melt and mixtures with other sodium halides. The nucleation mechanisms of both the solidification and the melting process at the atomic level are explored.

The structure of isolated photosystem I (PSI) complexes was studied using small-angle X-ray scattering (SAXS). The solution conformation of PSI showed that the polypeptide subunits at the periphery of PSI complex were partially unfolded and associated with detergent micelles.

The morphology, magnetic properties, crystallization mechanism and applications of the nanoparticles of amorphous Iron oxide are studied. The size of these amorphous particles predetermines the structure of the initial crystalline polymorph.

An in situ study, using optical microscopy is employed to investigate the morphology and growth kinetics of the lysozyme spherulites that are grown from sodium nitrate and sodium thiocyanate solutions through heterogeneous nucleation. The analysis of the spherulitic growth of hen egg-white lysozyme crystals reveal that the surface processes act as the late-limiting step, hence proving that polymorphic forms of the spherulites are less stable than the monoclinic form.

A combination of the growth probability method and several three-dimensional (3D) nucleation simulations is used to study the formation of polymorphs, wherein the nucleus size acts as a function of the driving force for crystallization. The study has found application in a large number of fields that includes a yellow isoxazolone dye, paracetamol and L-glutamic acid, as they show dominant nucleation of their stable form at all driving forces.

Crystallization processes in indomethacin can be observed below T(sub g) leading to different forms depending on the thermal treatment. A rapid and deep quench below T(sub g) leads to the metastable alpha-phase and a slow cooling close to T(sub g) gives rise to the stable gamma-phase.

The mechanism of intracrystalline mesopore formation by desilication in alkaline medium is controlled by tetrahedrally coordinated aluminum in MFI zeolite frameworks. A controlled mesoporosity development with preserved crystalline and acidic properties is enabled by the optimal molar Si/Al ratio in the range 25-50. This leads to more efficient zeolite utilization by improved diffusion characteristics.

Lamellar racemic twinning of chiral ammonium salts X=Br and X=I are found and investigated. The enantiomeric composition of the majority of the crystals obtained by crystallization from solutions of racemates, despite the chiral space group, is discovered to be racemic.

Measurements of chemical exchange events in the crystalline polycarbonate monomer 4,4'-isopropylidenediphenol (bisphenol A, BPA) via 2D 13C solid-state NMR shows slow, large-amplitude aromatic ring orientations. Experiments with multiple exchange times show that ring flips occur in all of the three unique conformers found in the crystalline unit cell of this compound, but in specific cases, two of the three unique molecules actually switch conformations.

The glass softening endotherm is interrupted by the crystallization exotherm, in the differential scanning calorimetry (DSC) scans of the annealed states of vapor-deposited, hyperquenched, and crystal-amorphized solids. The studies of hyperquenched kinetically frozen states of high fictive temperature of proteins would be valuable in investigating various stages of protein transitions.

The participation of a large amount of inserted charge in the Sb-doped sample can be possible due to the 'nanoscale factor' which causes rapid charging of the faradaic capacitance- related process. The 'nanoscale effect' provides the rapid ionic insertion into the nanostructured particles, while the Sb-doped atoms supply greater electronic conductivity.

The study on the thermal behavior of amorphous ALPHA-ALPHA-trehalose is highly dependent on the conditions used to perform thermal analysis experiments. The material may be recrystallize into a wide range of forms based on the dihydrate, the anhydrate or combination of both.

Dynamic crystallization and melting experiments were performed in small, stable and narrowly distributed nandroplets of miniemulsions, the regular and inverse systems were also examined. It showed that in both cases the temperature of crystallization in such droplets is significantly decreased as compared to the bulk material.

Investigations were made which aimed at the effects and mechanism of ultrasound-induced crystallization in tripalmitin (PPP) and trilaurin (LLL) suppercooled melts using situ synchrotron radiation time-resolved small-angle X-ray scattering (SAXS) and wide-angle X-ray scattering (WAXS) techniques. It was possible to describe the behavior of the most important parameters and the events that characterize the crystallization of these systems.

General bonding principles are used to predict the structure of individual nanocrystals in nanocrystalline materials with semiionic bonding. It is found that the proposed nanocrystals simultaneously fulfill strict criteria of stoichiometry, high coordination, and balanced charge distribution.

A new method is applied for preparation of yttria-stablilized zirconia(YSZ) nanocrystals. While crystallization occurs on the surface and interface of SrCO(sub 3) nanoparticles, the agglomeration of YSZ particles is inhibited.

The synthesis of lanthanide-doped phosphates in the coordinating solvent tris(ethylhexyl) phosphate is presented. The synthesis in tris(ethylhexyl) phosphate produced colloids of highly crystalline nanoparticles and a narrow particle size distribution.

It has been possible to develop a two-step crystallization process using dual templates. The amorphous framework of MCM-41 can be recrystallized, producing two sorts of MCM-41/ZSM-5 composites.

Research is presented concerning the use of single-crystal X-ray diffraction to determine the 1,n-dicarbazolyalkanes (C12H8N-(CH2)n-NC12H8) electron donor-acceptor complexes, where n = 1-5.

Research concerning the bond properties of polymer chains is presented. The external loading of entangled polymer chains results in rupture and this process is investigated by the use of molecular dynamics calculations.

An investigation of the effects of amines on high-pH zeolite crystallization reveals very strong affinity of the ZSM-5, ZSM-35 and MCM-22 frameworks for small amines. There is a beneficial pore-fill role for amines in many zeolite crystallizations.

Results demonstrate that progression of crystallization of colloidal Silicalite-1 with aqueous tetrapropylammonium in the open and closed systems can be monitored at defined composition and temperature. Data also indicate that the aggregation of molecules is mediated by the interaction potentials of the nanoslab planes carrying tetrapropylammonium cations.

A study describing the preparation by secondary crystallization or long crystallization times of thicker walled mesoporous MCM-41 silica with improved thermal and hydrothermal stability.

Issues concerning functionalization of Si-nc by 1-undecanol (UD-OH), 1-hexadecanol (HD-OH), 1-octanol (OC-OH) and 1,12-dodecanediol (DD-(OH)2) are discussed. Si-nc react with UD-OH, HD-OH, OC-OH and DD-(OH)2 to form alcohol capped Si-nc.

Investigation of crystalline nitric acid trihydrate properties at 195 K has been carried out by means of Car-Parrinello molecular dynamics calculations. Results demonstrate that a proton requires free energy to reach the center of the oxygen-oxygen pair.

The role of transition moment directions of chromophores in the prediction of CD and absorption spectra of biological macromolecules is discussed. Semiempirical MO theory gives a very good account of the transition moment directions in propionamide crystals.

The comparison of crystal structure of pyridine-ligated high-spin Ni(II) porphyrin complex with unligated low-spin Ni(II) complex is presented. Results indicate the induction of a Ni core expansion caused by conversion to high-spin Ni(II) in nonplanar sterically encumbered porphyrins.

It is possible for MoO3 nanocrystals with a layered structure to adhere to one sliding interface as a spacer. The nanocrystals then maintain a constant sliding contact area under different loads and produce load-independent friction.

Ab initio Hartree-Fock and many-body perturbation theory techniques can be used to simulate the structure and properties of molecular vacancy dimers in the high explosive cyclotrimethylene trinitramine C3H6N6O6 (RDX) crystal. High RDX anistropy is shown in the different binding energies and optical gap narrowing for the different mutual orientations of vacancy dimers.

Formation of cubic boron nitride in the MgB (sub)2-BN system at pressures to 6.8 GPa and temperatures to 2000 K has been studied by means of X-ray powder diffraction with synchrotron radiation. The position of cBN crystallization high-temperature boundary has been specified.

Research demonstrating the use of the hydrothermal method to study anataze crystallization from amorphous titatia is described. The effectiveness of water as a catalyst for anatase crystallization is illustrated.

The structure of small amines to the zeolite product obtained was related by means of a crystallization study. Certain noncyclic amines were specific for the formation of 10-ring zeolites such as ZSM-22 and ZSM-23 at SiO2/Al2O3 = 200. Highly crystalline ZSM-22 was yielded by ethylmethylamine and diethylamine while ZSM-23 was yielded by isopropylamine. Cyclic amines such as piperazine produced the 12-ring pore system ZSM-12 which was consistent with their larger size. A different set of zeolites was obtained from ZSM-35 and MCM-22 at lower SiO2/Al2O3 ratios (40).

A study was conducted on the crystalline mechanisms of zeolites. To further study zeolite synthesis, a silicon specimen was contained in an aged clear suspension. When subjected to intense heat, the crystallization resulted forming silicate-1. This process was followed by acidification, salting out, phase transfer into organic solvent and freeze-drying processes. Silicate-1 is a zeolite and a polymorph with MFI topology that can be synthesized by traditional hydrothermal gel method or by the clear solution process.

The use of the NMR free induction decay method to characterize the crystallization process of polyethylene is investigated. It is shown that the method allows the observation of the three different phases of crystallization. An extended Avrami model can be used to model the time development of different phases. Kinetic data on the crystallization process can also be determined via in situ NMR measurements.

A vertex addition-deletion procedure has been developed to study the growth mechanisms of fullerenes. The method is used specifically in examining the creation and annihilation of a (7,5) ring pair along with its motion. The (7,5) ring pair results from the insertion of a C2 molecule into the cavity of a hexagonal belt with 10 hexagons. The insertion produces a honeycomb lattice and two hydrocarbons with one and two (7,5) pairs. Results indicate that a hydrocarbon with a single pair behaves in a transition-state manner. The production of a hydrocarbon with two (7,5) pairs is a normal process compared to the formation of the honeycomb lattice.

Slow-scan voltammetric experiments were carried out to demonstrate that the stepwise electrochemical growth of the first and second monolayers of Ag2S on Ag(111) electrodes in aqueous hydrosulfide solutions can be seen as well-defined waves. The two monolayers have similar structures based on x-ray photoelectron spectroscopy and coulometric analysis. However, they have different free energies of formation since oxidative formation occurs at various electrode potentials.

The preparation and physical characteristics of oblate silver particles with diameters of 100 angstroms and protected by graphite oxide (GO) sheets that are 5 angstroms thick have been studied. The layer-by-layer self-formation of ultrathin films made up of polyelectrolytes and Ag-GO nanoparticles have also been examined. Results indicated that there are four steps in generating Ag-GO nanoparticles starting with the reduction of Ag cations on the surface of GO sheets followed by nucleation of small Ag clusters at different sites. The Ag clusters grow while the GO sheets around the Ag particles are bent.

A study was conducted to analyze the vibrational dynamics of alpha,alpha-trehalose-water solutions. O-H stretching region analysis was carried out using a decomposition of the isotropic spectra into an open and closed contribution along with a spectral stripping procedure. Experimental results indicated that trehalose hinders the crystallization process and minimizes the amount of freezable water.

Synchrotron X-ray diffraction at grazing angles of incidence was used to investigate the 2D crystallization of highly planar phthalocyanine pigments confined in a lipid Langmuir monolayer. The pigment, lipid and counterions were found to form a complex wherein the pigment plane is tilted with respect to the liquid surface. Results also revealed strong diffraction signals exhibited by both the alkyl tail region of the lipid and the lipid-pigment complex.

A study was conducted to analyze five di-muon-oxo bridged mixed-valence binuclear Mn(III)Mn(IV) complexes using multifrequency high-field electron paramagnetic resonance. The samples were prepared using recrystallized compounds and distilled anhydrous solvents. A Gunn diode microwave source was then utilized as the fundamental microwave source. Results indicated the feasibility of determining accurate estimates of the small g anisotropies of di-muon-oxo-bridged mixed-valence binuclear Mn(III)Mn(IV) complexes.

A study was conducted to analyze gallium oxides supporting different crystal phases, crystallinity and dispersion states using X-ray absorption spectroscopy. A series of Ga2O3 samples were prepared in different ways to determine a wide structural variety of Ga2O3. Experimental results indicated that gallium atoms supporting different coordination symmetry can be quantitatively estimated using a deconvolution analysis of X-ray absorption spectroscopy.

Acid/base equilibria is a key factor in the measurement of the steady-state and time-resolved fluorescence behavior of 1-pyrenecarboxylic acid (HPCA) in aqueous adipic acid solutions and the formation of a complex between HPCA and adipic acid with a formation constant of K(sub c) = 150 M(super -1). The lock-and-key probe molecule was used to ensure the proximity of the fluorescent moiety to the solution phase aggregation events of interest. The pH dependence of the chromophore response was observed in steady-state fluorescence data, while the rotational diffusion behavior of HPCA shows the presence of aggregates of adipic acid with the fluorophore.

The molecular ionic solid sodium chlorate has extensive applications in the pulp and agricultural industries. Computation studies were conducted to investigate the recrystallization and filtration of sodium chlorate. Crystallization of sodium chlorate was localized at the cubic space group P2(sub 1)3 (a = 6.575 Angstrom) with four NaClO3 formula units in the unit cell. The attachment energy of the crystal lattices was also measured. The findings were in agreement with observed morphologies in previous studies and revealed a chlorate rich {-1-1-1} form.

A study was conducted to carry out isothermal-isobaric molecular dynamics simulations of 1,3,5,7-tetraazacyclooctane (HMX) crystals. Molecular packing computations for the alpha, beta and photon phases of HMX were carried out. The impact of thermal effects on the structural parameters of various phases of the crystal was also analyzed. Experimental results indicated that Buckingham potentials developed for hexahydro-1,3,5-triazine can be utilized as a general nitramine potential.

A study was conducted to analyze the oxidation of sulfinic and sulfonic acids. The Lambda 2S UV-vis spectrophotometer was utilized to carry out standard kinetic studies. Results indicated that small organic sulfinic and sulfonic acids supported the same structure and existed in their zwitterionic forms in the crystalline form. Findings also showed that the sulfonic acids were stable in solution and decomposed very slowly.

A study was conducted to analyze the mid-infrared spectra of polycrystalline methyl fluoride between the 8K and 85K temperature range. The activation parameters of spinning diffusion and magnitude of the diffusion constant were obtained. Experimental results indicated no effects of the instrumental resolution on the obtained spectra. Findings also showed that homogeneous broadening correlated with vibrational and orientational relaxation processes.

A study was conducted to analyze the equilibrium structures and thermodynamic characteristics of dodecanethiol self-assembled monolayers on small and large gold nanocrystallites using molecular dynamics simulations. Several interactions were included in the molecular dynamics, including united-atom model potentials and sulfur-to-gold interatomic Morse potential. Results indicated that the disordering of the monolayers starts at the bundles' surfaces.