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Continuity Characterization and Evaluation of Rolled Polyester Coatings on Electrolytic Plates

Investigation of magnetic phase transformations in a system of Nd1−xBaxMnO3−δ (0≤x≤0.50) depending on the conditions of preparation

Investigations are performed of the crystal structure and magnetic and electromagnetic properties of single crystals (0.23 ≤x≤0.34) and polycrystals (0 ≤x ≤0.50) of an Nd1−x BaxMnO3−δ system of solid solutions. It is found that, for samples prepared in the air, the maximal Curie temperature (T C ) does not exceed 150…

Development of Wet Environmental TEM (Wet-ETEM) for In Situ Studies of Liquid-Catalyst Reactions on the Nanoscale

We present the development of in situ wet environmental transmission electron microscopy (wet-ETEM) for direct probing of controlled liquid-catalyst reactions at operating temperatures on the nanoscale. The first nanoscale imaging and electron diffraction of dynamic liquid hydrogenation and polymerization reactions in…

Coalescence of sessile drops

We present an experimental and theoretical description of the kinetics of coalescence of two water drops on a plane solid surface. The case of partial wetting is considered. The drops are in an atmosphere of nitrogen saturated with water where they grow by condensation and eventually touch each other and coalesce. A n…

Fabrication of compact silver nanoshells on polystyrene spheres through electrostatic attractionElectronic supplementary information (ESI) available: Preparation and characterization of PS spheres. Fig. S1: SEM micrographs of silver–latex composites. See http://www.rsc.org/suppdata/cc/b1/b110164c/

Nanoshells composed of close-packed silver nanocrystals have been fabricated on polystyrene spheres via direct electrostatic attraction at appropriate pH; the thickness and roughness of the shell can be readily controlled through a layer-by-layer technique.

POLYHEDRON DISTORTIONS IN TOURMALINE

Distortion parameters [� , � 2 , DI(Y‐O), DI(O‐ Y‐O), DI(O‐O)] have been calculated for cation polyhedra in tourmalines of different chemical compositions. Tourmalines with greater amounts of small, highly charged ions in the YO6 octahedron display greater bond-length distortion in Y. The size and charge of the occupa…

Surface Species Formed after NO Adsorption and NO + O2 Coadsorption on ZrO2 and Sulfated ZrO2: An FTIR Spectroscopic Study

Adsorption of NO and its coadsorption with oxygen on ZrO 2 and sulfated ZrO 2 have been studied by FTIR spectroscopy. It has been found that NO adsorption on ZrO 2 results in formation of N 2 O (2282, 2244, and 1233 cm - 1 ) and small amounts of nitro species (1443 and 1423 cm - 1 ), nitrates (1558, 1189, and 1057 cm…

Vibrations of amorphous, nanometric structures: When does continuum theory apply?

We investigate the low-frequency end of the vibrational spectrum in small (nanometric) disordered systems. Using numerical simulation and exact diagonalization for simple two-dimensional models, we show that continuum elasticity, applied to these systems, actually breaks down below a length scale of typically 30 to 50…

How To Derive and Parameterize Effective Potentials in Colloid−Polymer Mixtures

Polymer chains in colloid−polymer mixtures can be coarse-grained by replacing them with single soft particles interacting via effective polymer−polymer and polymer−colloid pair potentials. Here we describe in detail how Ornstein−Zernike inversion techniques, originally developed for atomic and molecular fluids, can be…

NMR comparative study of PbMg_1/3Nb_2/3O_3 and PbSc_1/2Nb_1/2O_3 local structure

The 93Nb and 45Sc NMR spectra in PbSc_1/2Nb_1/2O_3 (PSN) and PbMg_1/3Nb_2/3O_3 (PMN) disordered relaxor ferroelectrics at the temperature T > T_0 (T_0 is the temperature of the dielectric susceptibility maximum) have been studied. Spectra analysis was performed on the base both of the analytical description of NMR lin…

A Theoretical Search for the Optimum Giant Magnetoresistance

The maximum current-perpendicular-to-plane giant magnetoresistance is searched for in magnetic multilayers made of Co, Ni, and Cu with disorder levels similar to those found in room temperature experiments. The calculation is made possible by a highly optimized linear response code, which uses the impurity averaged Gr…

Quadratic Nonlinear Optical Properties ofN-Aryl Stilbazolium Dyes

The new salts trans-4′-(dimethylamino)-N-R-4-stilbazolium hexafluorophosphate (R = methyl, Me 1, phenyl, Ph 2, 2,4-dinitrophenyl, DNPh 3, 2-pyrimidyl, Pym 4, Scheme 1) have been prepared. Their electronic absorption spectra show intense, visible intramolecular charge-transfer bands, the energy (Emax) of which decrease…

The distance fluctuation criterion for melting: Comparison of square-well and Morse potential models for clusters and homopolymers

We explore the distance fluctuation criterion (“Lindemann criterion”) for melting transitions. Distances from average positions in accord with Lindemann, or interparticle distances, in accord with Jellinek and Berry or Etters and Kaelberer, are examined. The primary goal is to determine which of these offers the more…

Shear-Enhanced Crystallization in Isotactic Polypropylene. 3. Evidence for a Kinetic Pathway to Nucleation

In situ rheo-optical techniques are combined with synchrotron wide-angle X-ray diffraction (WAXD) to investigate the oriented crystallization precursors that develop upon strongly shearing an isothermal melt of polydisperse isotactic polypropylene (iPP). The “short-term shearing” experimental protocol, developed by Ja…

Mesostructured Forms of γ-Al2O3

gamma-Al2O3 is one of the most extensively utilized metal oxides in heterogeneous catalysis. Conventional forms of this oxide typically exhibit a surface area and pore volume less than 250 m2/g and 0.5 cm3/g, respectively. Previous efforts to prepare mesostructured forms of alumina resulted only in structurally unstab…

Large, Switchable Electrochromism in the Visible Through Far-Infrared in Conducting Polymer Devices

Advanced materials with large and dynamic variation in thermal properties, sought for urgent defense and space applications, have heretofore been elusive. Conducting polymers (CPs) have shown some intrinsic variation of mid- to far-infrared (IR) signature in this respect, but the practical utilization of this has rema…

Chiral Metallosalen Complexes: Structures and Catalyst Tuning for Asymmetric Epoxidation and Cyclopropanation

Optically active metallosalens are currently one of the most widely used catalysts for asymmetric synthesis. This is mainly due to the following reasons: various salen [N,N′-ethylenebis(salicyldeneaminato)] ligands form complexes with many metal ions and the resulting metallosalens adopt versatile structures, therefor…

Optical and structural investigation of ZnO thin films prepared by chemical vapor deposition (CVD)

Transparent and conductive ZnO thin films have been prepared by a method derived from chemical vapor deposition using Zn (C5H7O2)2 as Zn source. The deposited thin ZnO layers of ∼0.1 μm thickness on Si and InP semiconductor substrates, have been investigated with respect to the crystalline phase by X-ray diffraction (…

Kinetics and Mechanism of the Stannous Octoate-Catalyzed Bulk Polymerization of ε-Caprolactone

Bulk polymerizations of ε-caprolactone (CL) were conducted at 130 °C, in which the structure and amount of initiator were varied. Polymerization induction periods were observed and attributed to slow heat transfer and to the type of alcohol used as initiator. Induction periods persisted until virtually complete consum…

Localized Metallic Conductivity and Self-Healing during Thermal Reduction ofSrTiO3

The occurrence of metallic conductivity in SrTiO3 single crystals is reported for reduction under low partial pressure of oxygen at 800 degrees C. This transition is shown to result from the formation of a high concentration of vacancy defects along a network of extended defects within the skin region. A self-healing…