Materials Literature
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Abstract Morphology development during isothermal crystallization in equal molecular weight isotactic polypropylene ( i PP), syndiotactic polypropylene ( s PP), and i PP/ s PP blends was studied with time‐resolved simultaneous small‐angle X‐ray scattering (SAXS) and wide‐angle X‐ray diffraction (WAXD) with synchrotron…
The effects of the variation of different parameters in some hydrophobically modified polyacrylamides in aqueous polymer solution on their surface properties have been investigated. Two different hydrophobes, N, N -dihexylacrylamide (DiHexAM) and N -(4-butylphenyl)acrylamide (BPAM), have been used; the former was most…
The production of a microelectronic circuit is a complex operation, performed by dedicated, expensive machines that coat, expose, bake, develop, etch, strip, deposit, planarize, and implant. Each of these process steps must be executed by design in order for the final product to function properly. For controlling a pr…
We study the surface morphology evolution of ZnO films grown by pulsed laser deposition. Atomic force microscopy measurements show the existence of two growth regimes. Initially, the growth morphology is determined by shadowing effects due to the angular spreading of the plume in the 0.1 mbar oxygen working pressure.…
Abstract The objective of this work was to use both X‐ray and differential scanning calorimetry techniques in a comparative study of the lamellar and crystalline structures of heterogeneous and homogeneous ethylene‐α‐copolymers. The samples differed in the comonomer type (1‐butene, 1‐hexene, 1‐octene, and hexadecene),…
We report the structural solution of a one-dimensional ${\mathrm{Sb}}_{2}{\mathrm{O}}_{3}$ crystal incorporated within a helical (21,-8) single-walled carbon nanotube. The structures of both the encapsulated crystal and nanotube have been quantified using the phase image recovered via a modified object wave restoratio…
Short chains of Au 55 (PPh 3 ) 12 Cl 6 clusters were generated between tungsten tips on an SiO 2 surface, and their electrical behavior was studied. The clusters were deposited from solution by applying a voltage of 2 V between tips of 30 nm in distance. Current−voltage (I−V) measurements of the nanowires showed Coulo…
Electron spin echoes were performed on nitrogen-vacancy $(\mathrm{N}\ensuremath{-}V)$ centers in diamond using optical polarization and detection and 35 GHz microwave control. The experiments demonstrate an approach to quantum information in the solid state. A phase memory time of $3.6 \ensuremath{\mu}\mathrm{s}$ was…
Raman spectra were obtained from thin bundles containing just a few single-wall carbon nanotubes (SWNTs). These spectra exhibit new characteristics absent in the ensemble Raman measurements. A large variation in the radial breathing mode (RBM) Stokes to anti-Stokes Raman intensity ratio was observed for different meta…
Emission bands from Er 3+ ions on C 2 and S 6 sites of cubic Y 2 O 3 have been observed under 632.8 nm excitation. The well-known green hot band in the region of 520−540 nm and a new blue-green hot band in the region of 469−474 nm have been observed from Er 3+ on both sites. These hot bands are assigned to the 2 H 11/…
Calorimetry, small-angle X-ray scattering, and viscometry were used to study the structure of NaOH-water and cellulose-NaOH-water solutions in the range of 0-20% NaOH and 0-5% cellulose concentrations in the low-temperature region of -60 to 0 degree C. Pure NaOH-water solutions show a pseudoeutectic behavior with thre…
This study addresses the fouling of heat exchangers by coprecipitating inorganic salts. It investigates the effects of nondominant CaCO 3 on thermodynamics and kinetics of CaSO 4 precipitation as well as on scale structure. Even though precipitating salts coexist in industrial water systems, because of the complexity…
Using monomer-resolved molecular dynamics simulations and theoretical arguments based on the radial dependence of the osmotic pressure in the interior of a star, we systematically investigate the effective interactions between hard, colloidal particles and star polymers in a good solvent. The relevant parameters are t…
Transparent thin films of layered inorganic−organic nanocomposites were prepared by the sol−gel reactions of alkyldimethylmethoxysilane, alkylmethyldimethoxysilane, and alkyltrimethoxysilane in the presence of tetramethoxysilane followed by spin-coating. The macroscopic homogeneity and the nanostructural ordering of t…
Results of dielectric and resonance frequency ${(f}_{r})$ measurements below room temperature are presented for $\mathrm{Pb}({\mathrm{Zr}}_{x}{\mathrm{Ti}}_{1\ensuremath{-}x}){\mathrm{O}}_{3},$ $x=0.515$ and 0.520. It is shown that the temperature coefficient of ${f}_{r}$ changes sign from negative to positive around…
A photochromic nitrospiropyran moiety (Sp) has been covalently linked to a zinc (PZn) and to a free-base (P(H2)) porphyrin. In the resulting dyads (P(Zn)-Sp(c) and P(H2)-Sp(c)), the porphyrin first excited singlet states are unperturbed by the closed form of the attached spiropyran. Excitation of the spiropyran moiety…
The influence of an electric field on a poorly conductive membrane such as a lipid bilayer is studied theoretically. The unbalanced electric stress created by an ionic current across a non-perfectly flat membrane gives rise to a destabilizing surface energy enhancing undulations. The deformation of a membrane attached…
Recent experiments have shown that C60 can be positively field-doped. In that state, fullerene exhibits a higher resistivity and a higher superconducting temperature than the corresponding negatively doped state. A strong intramolecular hole-phonon coupling, connected with the Jahn-Teller effect of the isolated positi…
The present study reports the investigation of polyoxometalate catalyzed electron transfer from the conduction band of photoexcited TiO2 to molecular oxygen. The oxidation of 1,2-dichlorobenzene (DCB) was used as an index reaction for evaluating the photocatalyst systems TiO2-PW12O40(3-), TiO2-SiW12O40,4- and TiO2-W10…
Modeling and flow reactor experiments were used to study the kinetics of NO x storage/release on a Pt/BaO/Al 2 O 3 model catalyst. The mechanism for this concept can be divided into four steps: (i) NO to NO 2 oxidation on Pt, (ii) NO 2 storage on BaO, (iii) NO x release, and (iv) NO x reduction to N 2 . In this paper,…