Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
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 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.
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 $[{\…
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.
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…
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…
The temperature dependencies of the resistivity and magnetization of a series of Ni 2+ x Mn 1- x Ga ( x = 0-0.09) alloys were investigated. Along with the anomalies associated with ferromagnetic and martensitic transitions, well-defined anomalies were observed at the temperature of premartensitic transformation. The p…
Constitutive equations are derived for the viscoelastic behavior of particle-reinforced rubbers at isothermal loading with finite strains. A filled rubber is thought of as a composite medium where inclusions with high and low concentrations of junctions between chains are randomly distributed in a host matrix. The inc…
The photochemical and electrochemical properties of four chlorin-C60 or porphyrin-C60 dyads having the same short spacer between the macrocycle and the fullerene are examined. In contrast with all the previous results on porphyrin-fullerene dyads, the photoexcitation of a zinc chlorin-C60 dyad results in an unusually…
The synthesis and characterization of two members of a family of porous magnetic materials is described. The structures of Co4(SO4)(OH)6(C2N2H8)0.5*3H2O and Co4(SO4)(OH)6(C6N2H12)0.5*H2O and their thermal stability can be tailored via the choice of organic pillar. The interactions between the pillaring agent and the c…
The electron affinity (EA) $\ensuremath{\chi}$ of single crystal diamond (100) is determined as a function of hydrogen and oxygen coverage by a combination of work function and photoemission experiments. For the fully hydrogenated (100)-$(2\ifmmode\times\else\texttimes\fi{}1):\mathrm{H}$ surface an EA of $\ensuremath{…
The synthesis and study of so-called “nanoparticles”, particles with diameters in the range of 1−20 nm, has become a major interdisciplinary area of research over the past 10 years. Semiconductor nanoparticles promise to play a major role in several new technologies. The intense interest in this area derives from thei…
Abstract A hinged, photoresponsive polypeptide (PAzP) was prepared and the effect of the photochromic hinge on the dielectric and photoisomerization behavior of the polymer in solution was probed. Polymerization of N ‐carboxyanhydride of γ‐benzyl‐ L ‐glutamate was carried out with two different bifunctional photochrom…
Pt-containing nanocomposite catalysts were synthesized by deposition of [Pt(NH3)4]2+ complex ions on several samples of Al pillared clays, differing in the nature of the parent clay and in the pillaring procedure. In particular, we compared classical Keggin-Al13 pillared clays, with a rather open microporous network,…
The effect of a magnetic field ${B}_{\ensuremath{\perp}}$ on the resonant tunneling between different magnetic states of the molecular clusters ${\mathrm{Fe}}_{8}$ and ${\mathrm{Mn}}_{12}$ has been studied by measuring the magnetic specific heat of these compounds between $0.1 \mathrm{K}$ and $6 \mathrm{K}.$ At zero f…
We present electron diffraction and high-resolution electron microscopy measurements characterizing the structure of a Bi-based layered manganite. The crystal structure of ${\mathrm{Bi}}_{0.75}{\mathrm{Ca}}_{3.25}{\mathrm{Mn}}_{3}{\mathrm{O}}_{10}$ is orthorhombic and A centered (space group ${A2}_{1}22),$ with lattic…
Abstract Dendritic polyarylether 2‐bromoisobutyrates with different generations (Gn‐Br, n = 1–3) were prepared by reaction of the Fréchet‐type hydroxyl‐terminated polyarylether with 2‐bromoisobutyryl bromide and triethylamine. Gn‐Br as a macroinitiator for the controlled free‐radical polymerization of N ‐phenylmaleimi…
A series of dinuclear (phosphine)gold(I) complexes of the ambidentate 1,3,4-thiadiazoledithiolate ligand (SSS) were prepared in high yield from the corresponding (phosphine)gold(I) chlorides and K(2)(SSS) in methanol. While mononuclear components (R(3)P)AuCl with R(3) = Ph(3), Ph(2)Py, or Me(3) (1-3) gave open-chain c…
Two open-framework ammonium−iron borophosphates, black colored (NH 4 ) 0.4 Fe II 0.55 Fe III 0.5 (H 2 O) 2 [BP 2 O 8 ]·0.6H 2 O ( 1a ) (pale gray colored 1b with a powder X-ray diffraction pattern indicating an isotype relationship was also observed) and pale pink colored NH 4 Fe III [BP 2 O 8 (OH)] ( 2 ), were synthe…
ZrO 2 nanoparticles (10−400 nm) were produced by laser ablation deposition and studied by transmission electron microscopy. The particles were predominantly tetragonal (t-) phase with spherical shape. Relatively large t-ZrO 2 particles, however, showed {111} and {100} faces and tended to attach over well-developed {11…