Location of the Outer Shell and Influence of pH on Carboxylic Acid-Functionalized Poly(propyleneimine) Dendrimers
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Proton Relay in a One-Dimensional Hydrogen-Bonded Chain Composed of Water Molecules and a Squaric Acid Derivative
The crystal structure of a hydrated crystal of bis(squaryl)biphenyl (BSQB*4H2O), in which two squaric acid moieties are connected with a 4,4'-biphenyl unit, was characterized by the presence of a one-dimensional hydrogen-bonded chain composed of BSQB and water molecules. X-ray crystallographic analysis showed that BSQ…
Magnetic domain-wall width inLa0.7Ca0.3MnO3thin films measured using Fresnel imaging
Magnetic domain walls in ferromagnetic ${\mathrm{La}}_{0.7}{\mathrm{Ca}}_{0.3}{\mathrm{MnO}}_{3}$ films ${(T}_{C}\ensuremath{\sim}260\mathrm{K})$ have been studied in the transmission electron microscope. Epitaxial films grown on ${\mathrm{SrTiO}}_{3}$ and ${\mathrm{NdGaO}}_{3}$ substrates were prepared using a focuse…
Modified natural phosphates: easily accessible basic catalysts for the epoxidation of electron-deficient alkenes
Natural phosphate is basic enough to promote the epoxidation of electron-deficient alkenes with dilute aqueous hydrogen peroxide. A simple modification with sodium nitrate leads to the probably most active, water compatible and recyclable basic catalyst described for this reaction. It promotes the epoxidation of a lar…
A New Polymorph of ZrW2O8 Synthesized at High Pressures and High Temperatures
Pressure-induced amorphization of materials with negative thermal expansion is believed to arise from uncorrelated tiltings of polyhedra, kinetically frozen in an orientationally disordered state at room temperature. The transition to an amorphous phase in zircon tungstate ZrW 2 O 8 occurs above 1.5 GPa upon cold comp…
CeO2–ZrO2 binary oxides for NO x removal by sorption
Removal of NOx (NO in the presence of O2) by CeO2–ZrO2 binary oxides was investigated. CeO2–ZrO2 prepared by a modified sol–gel method [CZ(SG)] showed high NOx sorption capacity, while CeO2–ZrO2 prepared by a coprecipitation method [CZ(CP)] was not effective. In both cases, NOx was found to be removed by adsorption on…
Adiabatic and non-adiabatic small-polaron hopping conduction in La1−xPbxMnO3+δ(0.0 ≤x≤ 0.5)-type oxides above the metal–semiconductor transition
Above the semiconductor-to-metallic transition (SMT) temperature ( T p ), transport properties of the La 1− x Pb x MnO 3+δ (0 ≤ x ≤ 0.5)-type mixed valence oxides with T p between 230 and 275 K (depending on x ) have been thoroughly examined for a small-polaron hopping conduction mechanism of the carriers. Although th…
Liquid‐crystalline organic–inorganic hybrid polymers with functionalized silsesquioxanes
Abstract Liquid‐crystalline (LC) hybrid polymers with functionalized silsesquioxanes with various proportions of LC monomer were synthesized by the reaction of polyhedral oligomeric silsesquioxane (POSS) macromonomer with methacrylate monomer having an LC moiety under common free‐radical conditions. The obtained LC hy…
Blue emission from cysteine ester passivated cadmium sulfide nanoclusters
A one-pot synthesis is reported of water-soluble cadmium sulfide nanoclusters capped with cysteine ester, with an average size of 2.0 nm and fluorescing in the blue region, establishing the possibility of using these as fluorescent biological probes.
Magnetic-Shielding Calculations on Al42- and Analogues. A New Family of Aromatic Molecules?
The molecular structures, the nuclear magnetic shieldings, and the aromatic ring-current shieldings (ARCS) have been calculated for Al 4 2-, Al 4 Li -, and Al 4 Cu - at the Hartree−Fock (HF) level, the second-order Møller−Plesset (MP2) level, the coupled-cluster singles and doubles (CCSD) level, and the coupled-cluste…
Impact of Nitrate-Mediated Microbial Control of Souring in Oil Reservoirs on the Extent of Corrosion
The effect of microbial control of souring on the extent of corrosion was studied in a model system consisting of pure cultures of the nitrate-reducing, sulfide-oxidizing bacterium (NR-SOB) Thiomicrospira sp. strain CVO and the sulfate-reducing bacterium (SRB) Desulfovibrio sp. strain Lac6, as well as in an SRB consor…
Influence of Processing Conditions on Structures of 3D Ordered Macroporous Metals Prepared by Colloidal Crystal Templating
This paper presents general methods of preparing three-dimensionally ordered macroporous (3DOM) metals or alloys via templated precipitation and subsequent chemical conversion of metal salts (acetates, oxalates) within colloidal crystals of poly(methyl methacrylate) (PMMA) or polystyrene (PS) spheres. Three approaches…
MoSe2 and WSe2 nanotubes and related structures.
MoSe2 and WSe2 nanotubes are obtained by the reduction of the corresponding triselenides in hydrogen or by the decomposition of the ammonium selenometallates in a hydrogen atmosphere.
Observation of Large Changes in the Band Gap Absorption Energy of Small CdSe Nanoparticles Induced by the Adsorption of a Strong Hole Acceptor
When butylamine in relatively high concentrations (0.1−0.25 M) is added to a colloidal solution of CdSe nanoparticles (NPs) that are approximately 1.6 nm in diameter, the band gap absorption changes from a broad, relatively weak absorption centered at 445 nm to a narrow, relatively strong absorption centered at 414 nm…
Platinum-Containing Hyper-Cross-Linked Polystyrene as a Modifier-Free Selective Catalyst for l-Sorbose Oxidation
Impregnation of hyper-cross-linked polystyrene (HPS) with tetrahydrofuran (THF) or methanol (ML) solutions containing platinic acid results in the formation of Pt(II) complexes within the nanocavities of HPS. Subsequent reduction of the complexes by H2 yields stable Pt nanoparticles with a mean diameter of 1.3 nm in T…
Sulfonic acid functionalized mesoporous MCM-41 silica as a convenient catalyst for Bisphenol-A synthesis
Sulfonic acid groups anchored to the surface of mesoporous MCM-41 silica have been identified with S K-edge XANES spectra and the material is an efficient catalyst for the liquid phase condensation of phenol with acetone to form Bisphenol-A with high selectivity.
Large thermopower in a metallic cobaltite: The layered Tl-Sr-Co-O misfit
The magnetic, transport, and thermoelectric properties of a Tl-based misfit cobaltite have been investigated. Although this material exhibits a metallic behavior, the thermopower (Seebeck) is large, with room temperature values close to +90 \ensuremath{\mu} V/K. Compared to previously studied misfit cobalt oxides $[{\…
Sn-MCM-41—a heterogeneous selective catalyst for the Baeyer–Villiger oxidation with hydrogen peroxideElectronic supplementary information (ESI) available: XRD pattern of as-prepared Sn-MCM-41. See http://www.rsc.org/suppdata/cc/b1/b105927k/
A new heterogeneous catalyst, Sn-MCM-41, is described for the Baeyer-Villiger reaction with hydrogen peroxide which selectively activates the carbonyl function for the nucleophilic attack by the oxidant, with high chemoselectivities when double bonds are present in the molecule.
Interplay of structure and transport properties of sodium-doped lanthanum manganite
The crystal structure, magnetic and electrical transport properties of the sodium-doped lanthanum manganites La 1- x Na x MnO 3 (0.07⩽ x ⩽0.40) have been studied in detail using x-ray powder diffraction, atomic absorption spectroscopy, a SQUID (superconducting quantum interference device) magnetometer and the four-pro…
Effects of Filtration Seeding on Cell Density, Spatial Distribution, and Proliferation in Nonwoven Fibrous Matrices
The cell seeding density and spatial distribution in a 3-D scaffold are critical to the morphogenetic development of an engineered tissue. A dynamic depth-filtration seeding method was developed to improve the initial cell seeding density and spatial distribution in 3-D nonwoven fibrous matrices commonly used as tissu…