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The influence of different interfacial chemical environments of the 3C-SiC nanoparticles fabricated by electrochemical etching of bulk 3C-SiC substrates is discussed in detail. The results provide insight into the surface chemistry, solvent nature, and surface charges on the photoinduced absorption and luminescence of the nanoparticles at room temperature.

Acid-base titrations, cadmium adsorption assays and Fourier transform infrared spectroscopy (FT-IR) are used for characterizing the surface reactivities of Hymenobacter aerophilus cells with intact extracellular polymeric substances (EPS) (WC) or stripped of EPS (SC) and purified EPS alone. The presence of EPS has corresponded to an increase in the number and type of functional groups on the surface of H. aerophilus that is reflected by increased metal adsorption relative to that for EPS-free cells.

Sum-frequency spectroscopy is applied to investigate the interaction of hexane, acetonitrile and water with an organic surface, a monolayer of 16-methoxyhexadecanethiol adsorbed on gold. The technique affords detection of the light emitted at the sum frequency and simultaneous pulsing of a fixed-frequency visible laser and a tunable infrared laser on an interface. The sum-frequency spectra of monolayers of octadecanethiol and 16-methoxydecanethiol on gold in contact with air, hexane-d14, acetonitrile-d3 and water displayed dependency on the surface structure.

The medium-energy ion scattering technique is employed to explain the characterization of the various nanostructures present at the surface of a substrate. The energy loss taking place at the backscattering collision is shown to highly affect the shape and size distribution of the nanoparticles.

The studies have shown HF etching of oxidized silicon carbide (SiC) has led to a very different surface termination, whether the surface is carbon or silicon terminated. The surface properties have affected the ability to chemically functionalize the surface and hence affect how SiC is used for biomedical applications.

Threshold strain needed for a thermally activated dislocation nucleation from a Ni surface step is measured by using an atomistic-based reduction reaction pathway analysis. The coherency strain caused by a lattice mismatch between Ni and Cu has not produced enough driving force for the dislocation nucleation.

The effect of surface chemistry in plasma etching of multicomponent oxides is examined by the measurements of the ion energy dependence of the etch yield. In the case of CBN films etched in an inductively coupled [Cl.sub.2] plasma, the studies have shown that the chlorine uptake is inhibiting the etching reaction, with the desorption of nonvolatile Nb[Cl.sub.2] and Ba[Cl.sub.2] compounds being the rate-limiting step.

Byline: P. Tercier, P. Muhlemann, R. Stubi, A. Chassot The parameterisation of the surface energy balance in short-range dispersion models is currently receiving increased attention. Most of the current treatments rely on adaptations of the original schemes of Van Ulden and Holtslag, and Berkovicz and Prahm. These parameterisations are based on conventional meteorological network measurements of e.g. wind, temperature and humidity. The ground heat flux is expressed as a constant fraction of the net radiation, as is the sensible heat flux. An alternative approach relates the ground heat flux to the temperature gradient within the soil. These schemes are compared with direct measurements. The aim is to test their ability to simulate the daily heat-flux cycle under various meteorological conditions.

The effect of the structuring of interfacial water, induced by surface charge, on the ultrafast vibrational dynamics of the O-H stretch in the hydrogen bonded spectral region is examined at the [H.sub.2]O/fused silica interface. The longer vibrational lifetimes is because of reduced intermolecular coupling resulting from incomplete solvation of the interfacial water species.

A robust peptide-based coating technology with ability to easily modify the surface of titanium (Ti) metal through noncovalent binding is described. The PEGylated-peptide coating exhibited potential ability to resolve two major problems commonly associated with implanted metals, such as nonspecific protein adsorption and bacterial colonization and the facile one-step modification process would also facilitate the point-of-care application of these coatings in the surgical suite.

The surface of the layered III-VI chalcogenide semiconductor GaTe is subjected to various chemical treatments used in device fabrication to determine the effect of the resulting microscopic surface composition on transport properties. The measurements are correlated to understand the effect of surface chemistry on the electronic structure at these surfaces with the aim of minimizing the surface leakage currents for radiation detector devices.

An in-depth model is developed for the transient behavior of metal atoms adsorbed on the surface of GaN. The suggested model has helped in understanding the surface kinetics of GaN, has provided an indirect method of monitoring the kinetic evolution of these surfaces, and has introduced a novel method of in situ growth rate determination.

The device performance of organic light-emitting diodes which was significantly improved by inserting a Ba coverage ( Ba) of 1 nm between tris(8-quinolinolato)aluminum (III) ([Alq.sub.3]) and the cathode is reported. The improvement in the OLED is attributed to the lowering of the electron-injecting barrier height that was induced by the formation of a new gap state from an interfacial chemical reaction, as well as band bending due to Fermi level pinning.

A new simulation method is described for nonuniform polymer solutions between planar surfaces at full chemical equilibrium. The method has used a grid of points in a two-dimensional thermodynamic space, labeled by space area and surface separations.

The Langmuir monolayer of aequorin and apoaequorin is analyzed by using infrared reflection-absorption spectroscopy (IRRAS) and polarization-modulated IRRAS technique. The different behaviors of aequorin and apoaequorin at the air-water interface are described by the fact that aequorin formed dimers at the air-water interface but apoaequorin is a monomer and it is difficult for a dimer to be tilted by the compression of the Langmuir monolayer.

The zinc oxide (ZnO) thin films are obtained by the atomic layer deposition (ALD) method by using diethyl zinc and water precursors at temperatures ranging from 100 to 200 degree centigrade. The studies have shown that extremely low temperature growth by ALD has resulted in high quality ZnO thin films with inefficient nonradiative decay channels and with thermodynamically blocked self-compensation processes.

The combination of a surface chemistry approach and a FRET-based biosensor is employed to demonstrate the dynamics of various RhoA GTPase activation in cells on patterned substrates. The results show that the RhoA activity is much higher at the periphery than inside the body of the cell.

The quantitative real-time detection of single-stranded oligonucleotides with silicon nanowires (SINWS) in physiologically relevant electrolyte solution is demonstrated. While the implication is that SINWS can be utilized to quantitate the solution-phase concentration of biomolecules at low concentrations, the importance of surface chemistry for optimizing biomolecular sensing with silicon nanowires is also demonstrated.

A larger aromatic pi-system is synthesized that shows extraordinarily high stability and an effective suppression of aggregation. Results reveal that the bulk properties in an extruded fiber as well as on the surface showed a columnar self-assembly including a phase in which homeotropic alignment on a substrate is observed.

Reaction between 1,2-dibromobenzene and the Si(111)-7x7 surface is studied theoretically on the DFT(B3LYP/6-31G(d) level. Calculations suggest that the reaction occurs spontaneously at room temperature through a covalent attachment of the intact 1,2-dibromobenzene to the silicon surface.

1s2p Resonant inelastic X-ray scattering (RIXS) spectroscopy is measured for a series of iron oxides, including octahedral and tetrahedral Fe(super II) and Fe (super III) systems, crystal-field multiplet simulations are used to analyze their spectral shapes. The full power and possibilities of 1s2p RIXS needs an overall resolution of 0.3 eV and this yields a technique with more detailed information than K-edge and L-edge X-ray absorption combined, obtained in a single experiment.

The role of surface science in the surface reactivity to contribute to the understanding of biodegradation kinetics and controlled drug release mechanisms for some important biological polymers such as poly(glycolic acid) and poly(lactic acid) is reviewed. Result not only showed a fundamental understanding of hydrolytic surface degradation kinetics as a model for the drug delivery systems but also toward the design and formulation into new devices.

The study examined the adhesion of graphite to functionalized polyester surfaces using a range of qualitative and quantitative measures of theoretical adhesion. The theoretical results suggested one mechanism to reduce adhesion to carbonaceous solids, which is to increase atomic roughness using strongly hydrophilic or alternatively strongly hydrophobic substituents.

The study shows the development of countermeasures and therapeutics for Clostridium botulinum neurotoxins (BoNTs) because of their extreme toxicity and potential misuse as biowarfare agents. The results show the high-resolution structure of active BoNT/F catalytic domain in two crystal forms for modeling the substrate binding and identifying the S1' subsite and the putative exosites are different from BoNT/A or BoNT/B.

A simple chemical method for synthesizing surface-attached one-dimensional (1D) gold nanorods/single-crystalline metal (Au NRs/SWCNT) heterojunctions is reported. The new structures are found to have fundamental interests and promising applications.

The surface composition of Al2O3, V2O5 and luminovanadate oxide, 'V-Al-O', is studied to reveal time-dependent irradiation damage of samples. The interaction of Mg K(sub alpha) radiation with Al2O3, V2O5 and V-Al-O causes modifications of the surface composition and eventually, of the metal oxidation state.

The transient gravimetric method is used to measure the pore and surface diffusion of carbon dioxide (CO2) and ethylene (C2H4) in the nanopores of ordered mesoporous silica fibers about 200 micrometer in length. The results show that the surface diffusion coefficients for the ordered mesoporous silica fibers are about 1 order of magnitude larger than the nonordered mesoporous alumina or silica with similar pore size.

Temperature programmed desorption and reflection adsorption infrared spectroscopies are used to characterize the adsorption and surface chemistry of 2-butanol and propylene oxide on Pt(111). 2-butanol, monolayer bonding takes place through the oxygen atom and with the C-O bond close to perpendicular to the surface.

The (0001) surface of alpha-Al2O3 single crystals is imaged by atomic force microscopy in water. The observed hexagonal lattice arrangement has a period of 4.7 Angstrom in good agreement with the known bulk unit cell.

A facile route to pattern polymer surfaces with the aid of compressed CO2, termed the compressed CO2-assisted imprint method is reported. The patterned structures can be tuned by changing CO2 pressure and temperature in the imprinting process.

A novel self-assembled microstructure, nestlike Mg5(CO3)(sub 4)(OH)(sub 2).4H2O spheres is formed by a self-assembly of nanosheets in the hydrothermal process. The unique MgO microstructure with high surface areas may possess promising applications as the sorbent for chemisorption and destructive adsorption of various pollutants.

Ultralong single-crystalline TiO2 nanowires were prepared by a simple, low-cost solvothermal process. Silver nitrate, neodymium chloride, ceric nitrate, stannic chloride hydrate, and cadmium chloride were used as metal sources and deposited by reduction on the surface of TiO2 nanowires.

Palladium nanocrystals were grown on a nanostructured SrTiO3(001) surface and annealed in ultrahigh vacuum at 620 degree celcius. This leads to the so-called strong metal-support interaction (SMSI) state, characterized by encapsulation of the metal clusters with an oxide layer.

The chemistry of carbon dioxide at the adsorbed water iron-oxide interface is investigated. Adsorbed water enhances CO2 uptake, undergoes isotope exchange with CO2 in O(18)-labeled experiments, and influences the chemical nature of the predominant adsorbed product on the surface from bicarbonate to carbonate.

The electroless deposition chemistry of metal ions can be spatially defined by block copolymers to produce patterned metal nanoparticles on Ge, Si, ImP and GaAs. The electronic characteristic of these interfaces is investigated.

The Monte Carlo and modified embedded atom methods are used to investigate the surface structures of cubo-octahedral Pt-Mo nanoparticles. It is found that decreasing the size or increasing the Pt concentration leads to higher Pt concentrations but fewer Pt-Mo pairs in the Pt-Mo nanoparticle surfaces.

The interaction of pyridine with the catalyst is examined by investigating the surface acidity of an activated eta-alumina catalyst. The surface structure of the activated catalyst is redefined as comprising weak, medium-weak, medium-strong, strong Lewis acid sites.

A study of homogeneous rubbing followed by crystallization for poly(3-hexylthiophene) (P3HT) thin films is reported. The possibility to realize modifications on P3HT surfaces with spatial and geometrical control of the nanorubbing using the stylus of an atomic force microscope (AFM) is demonstrated.

A synthesis of infinite one-dimensional polyoxometalates (POMs) is carried out, which is based on the lanthanide and monolacunary Keggin [SiW(sub 11)O(sub 19)](super 8-) with a stoichiometric ratio of 1:1. The results obtained suggest that POM-based vesicles also exist in the surfactant-encapsulated heteropolyoxotungstate systems, and the sizes are larger than those in the polyoxomolybdate-based solution.

NO(sub x) storage over hexagonal BaCO3(110) is investigated using first-principle calculations with focus on the importance of surface decarbonation. Upon decarbonation, supported BaO quasi-molecules are formed and a small drive toward (BaO)(sub n) luster formation is predicted.

The relationship between the structure of yttrium-stabilized zirconia (YSZ) and ZrO2 catalysts and their ability to activate N2O and O2 is studied by determination of catalytic properties. N2O can be activated at structural defects and intrinsic oxygen vacancies [Zr'(sub Zr-)V(super ..)(sub O-)Zr'(sub Zr)] and forms two types of oxygen species (alpha-O and beta-O) on the surface, respectively.

A study is conducted that compares the folding of two polypeptides, bovine carbonic anhydrase (BCA) and peracetylated BCA having the same sequence of amino acids but differing by 18 formal units of charge, from a solution containing denaturing concentrations of sodium dodecyl sulphate. The study suggests that large differences in the net charge of polypeptide have no significant influence on the structure, ability to refold or its rate.

The molecular mechanisms involved in the formation and stability of protein-stabilized foams and emulsions is analyzed. Proteins play an important role as macromolecular surfactants in foam and emulsion type food products, and the functioning of proteins is determined by their structure and properties in the adsorbed layers at air-water and oil-water interfaces.

Simulations of self-assembled monolayers are performed to interpret experimental measurements of ultrafast approximately 1GPa planar shock compression dynamics probed by vibrational sum-frequency generation (SFG) spectroscopy. Isothermal compressions help explain the time dependence of shock spectra but generally underestimate the magnitude of SFG signal loss because they do not include effects of high strain-rate dynamics and shock front and surface irregularities.