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。
The synthesis, X-ray structure, and magnetic susceptibility characterization of a hydroxo-bridged complex, (&mgr;-hydroxo)bis((tetraphenylporphinato)manganese(III)) perchlorate, {[Mn-(TPP)](2)(OH)}ClO(4), are described. The complex is readily prepared by a controlled hydrolysis of monomeric diaquo(tetraphenylporphinat…
The physical and chemical properties of polypyrrole (PPy) derivatized at the 3-position with dimethoxybenzyl and dihydroxybenzyl functionalities via a novel high-yield pathway were evaluated for pH response. The monomers were electrochemically polymerized with perchlorate dopant in a propylene carbonate electrolyte so…
Certain polydiene rubbers can be doped by iodine to become electrically conducting. In particular, the conductivity of trans -1,4-polybutadiene can be increased by 8 orders of magnitude upon conjugation and self-doping by iodine at room temperature, whereas cis -1,4-polybutadiene cannot be made conducting by reaction…
Magnetic and transport properties of single crystals of ${\mathrm{TbNi}}_{2}$${\mathrm{B}}_{2}$C have been investigated by ac susceptibility, dc magnetization, specific heat, and resistance measurements. The compound shows highly anisotropic magnetic properties which come about as a result of the Tb magnetic moments l…
PZT thin films for microsensors and microactuators were prepared from lead acetate and zirconium, titanium alkoxide solution by sol-gel processing. High-performance, crack-free, thin (3.1μm) films were acquired by multiple coating, and high-temperture annealing.PbO evaporation occurred on firing. This is caused by the…
A facile synthesis that combines the use of an easily polarizable thiophene ring and a ring-locked triene as efficient conjugating moieties is employed to simultaneously enhance molecular nonlinearity (as high as 13000 × 10–48 esu) and thermal stability; incorporating this highly nonlinear chromophore in polyquinoline…
Diaminopimelate dehydrogenase catalyzes the NADPH-dependent reduction of ammonia and L-2-amino-6-ketopimelate to form meso-diaminopimelate, the direct precursor of L-lysine in the bacterial lysine biosynthetic pathway. Since mammals lack this metabolic pathway inhibitors of enzymes in this pathway may be useful as ant…
Utilization of a Cs-promoted Cu/ZnO/Cr 2 O 3 catalyst as a first low-temperature bed and a Cs-promoted ZnO/Cr 2 O 3 catalyst as a second high-temperature bed significantly promoted the productivity of 2-methyl-1-propanol (isobutyl alcohol) from H 2 /CO synthesis gas mixtures. While the conversion of CO to C 2+ oxygena…
ADVERTISEMENT RETURN TO ISSUEPREVNoteNEXTSynthesis and Characterization of H-Shaped PolyisopreneAbdelkrim Hakiki, Ronald N. Young, and Thomas C. B. McLeishView Author Information Department of Chemistry, The University of Sheffield, Sheffield S3 7HF, United Kingdom, and IRC in Polymer Science and Technology, The Unive…
Samarium cobalt nanoparticles were prepared by ball milling under argon, both with and without surfactant. X-ray diffraction indicated a single SmCo/sub 5/ phase, with an average size of 25 nm from Debye-Scherrer analysis of the peak widths, but a broad size distribution based on TEM. SQUID magnetometry yielded the co…
Hydrotalcite structures containing copper, magnesium and aluminium in the metal hydroxide layers have been investigated for their potential as precursors to the formation of catalysts for the decomposition and reduction of nitrogen oxides. These CuIIMgIIAlIII hydrotalcites are catalytically active towards both the dec…
Polymers grafted or otherwise immobilized at surfaces are often used to stabilize particle suspensions in situations where nonspecific colloidal forces or specific chemical bonds act to coagulate the particles. Although the motivation is clear, criteria for steric stabilization are not well established for environment…
Redispersion of sintered Pt (0.6−1.0%)/Al 2 O 3 catalysts at 773 K under HCl/H 2 O/O 2 /N 2 atmospheres was studied by hydrogen chemisorption, temperature-programmed reduction (TPR), transmission electron microscopy (TEM) and in situ X-ray absorption spectroscopy (EXAFS) experiments. TPR and H 2 chemisorption results…
Fe(3,6-DBSQ)(3) has been prepared by reacting 3,6-di-tert-butyl-1,2-benzoquinone with Fe(CO)(5). The complex has been characterized structurally [orthorhombic, Pbca, a = 18.277(5) Å, b = 11.634(3) Å, c = 39.903(10) Å, V = 8485(4) Å(3), Z = 8, R = 0.063], electrochemically, and magnetically. Ligand-based redox couples…
In systemic radiation therapy, the absorbed dose distribution must be calculated from the individual activity distribution. A computer code has been developed for the conversion of an arbitrary activity distribution to a 3-D absorbed dose distribution. The activity distribution can be described either analytically or…
Here we discuss macroemulsions stabilized by interfacial colloidal films, in terms of the basic processes of colloid nucleation, colloid flocculation, and assembly in interfacial films. By monitoring the droplet-diameter, we present the effect of a variety of surfactants, additives, and organic solvents, as well as th…
A new quinary rare earth sulfide-halide compound has been synthesized and its structure determined by single-crystal X-ray diffraction. LaCa(2)GeS(4)Cl(3) crystallizes in the noncentrosymmetric hexagonal space group -P6(3)mc (No. 186) with Z = 2, a = 9.731(1) Å, and c = 6.337(1) Å. Lanthanum and calcium are mixed on a…
We have investigated the growth shape of two-dimensional (2D) poly(ethylene terephthalate) spherulites using a transmission electron microscope technique in order to examine the role of a diffusion-controlled mechanism in the growth process. At the growth front of the 2D spherulites, we found a terrace-like morphology…
An ab initio molecular orbital study is undertaken on the adsorption of N 2, O 2, and C 2 H 4 (adsorbate) on Ag−zeolite and Ag halides (adsorbent). Geometry optimization is performed at the HF/3-21G level, while MP2/3-21G with natural bond orbital calculations are performed to obtain energies, atomic charges, orbital…
Deposition of anatase TiO2 thin films on soda-lime glass has been achieved by firing an adhered precursor titanium(IV) complex of ethylenediamine-N,N,N′,N′-tetraacetic acid (H4edta) between 450 and 550 °C in air. The coating solution was prepared by the reaction of a neutral [Ti(H2O)(edta)] complex, obtained from TiCl…