Materials Literature
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Strong exciton coupling occurs between adjacent pairs of naphthyl chromophores in the chiral sodium and europium complexes of L 1 ; in the constitutionally isomeric complexes of L 2 , intramolecular excimer formation is observed and both sets of Eu complexes give a well defined, metal-based circularly polarised emissi…
A method for the preparation of amorphous Fe 3 O 4 powder with a particle size of ca. 25 nm is reported. Amorphous Fe 3 O 4 powder can be simply synthesized by slowly exposing amorphous Fe powder to the air. The amorphous properties of Fe 3 O 4 nanoparticles were characterized by X-ray diffraction, Mössbauer spectrosc…
Abstract Based on a comprehensive review of the literature on textile fabric porosity, air permeability, and related research on fabric geometry, a study of the relationships between air permeability measurements and fabric pore size was undertaken using liquid porosimetry. Experiments were conducted on ten woven text…
The reaction of phenoxide ion with the copper(II), nickel(II) and free-base 2-nitro-5,10,15,20-tetraphenylporphyrins, 1–3 respectively, has been investigated as a means of introducing inwards-directed functionality to the periphery of pre-existing porphyrin systems. It has been found that phenoxide ion shows highly se…
4,5-Dipentyldiiminoisoindoline 1 reacts with hexachlorodisilane (Si 2 Cl 6 ) to give the ring-contracted hydroxysilicon-α,β,γ-triazatetrabenzcorrole 4 which in solution photolyses giving the ring cleavage compounds 5 and 6; the stability of triazatetrabenzcorroles 4 and 7 with silicon and germanium as central elements…
Zeolite HSZ-360 promotes the conversion of hydroxylated biaryls to dibenzofuran derivatives in satisfactory yields and excellent selectivities. Clays and amorphous silica–alumina are inert or less effective.
The thermal conductance of 8- to 200-nm-thick films of SiO and MgO is measured in the 2 temperature range 78 - 400 K using the 3 omega method. The apparent thermal conductivity of the films is reduced by the finite thermal conductance of the interfaces between the metal film heater and the dielectric layer, and betwee…
The anhysteretic behaviour of nickel has been studied by two methods: the conventional field cycling method, and by thermal demagnetization followed by cooling in an applied field. The results show that the field cycling method does not achieve thermal equilibrium, the anhysteretic magnetizations differing by as much…
The adsorption of the different species X and CX 3 on an X-terminated diamond (111) surface (X = H, F, Cl, Br) has been investigated structurally and energetically, using a cluster approach and two different types of quantum mechanical methods: the ab initio molecular orbital (MO) method and the first-principle densit…
A series of four "mixed" bis(thiosemicarbazone) keto aldehyde derivatives containing dissimilar thiosemicarbazone functions were synthesized and evaluated as ligands for preparation of radiocopper-labeled radiopharmaceuticals. The pyruvaldehyde-based mixed bis(thiosemicarbazone) ligands CH3C[=NNHC(S)NH2]CH[=NNHC(S)NHM…
The initial events (virus adsorption and fusion with the cells) in the replicative cycle of human immunodeficiency virus (HIV) can serve as targets for the antiviral action of metal-binding compounds such as polyanionic compounds (polysulfates, polysulfonates, polycarboxylates, polyoxometalates, and sulfonated or carb…
This paper presents an approach for obtaining science-based answers to practical vacuum device problems. The question "How to translate scientific knowledge to design and operation practice" is rephrased to the more productive question "What research activities are required to provide science-based answers to practica…
BrNO 2 is produced by the heterogeneous reaction of ClNO 2, highly diluted in He, with an aqueous bromide solution and subsequent trapping at −155 °C. The crude product is purified by trap to trap condensation and fractional sublimation in vacuo. At 300 K and a pressure of 1 mbar, a half-life of about 1 h is observed.…
Les essais d'entartrage réels sont toujours longs à mettre en œuvre. Aussi a-t-on mis au point des essais d'entartrage accélérés. Cependant les diverses méthodes utilisées, électrochimiques ou autres, ne sont pas toujours représentatives des phénomènes réels d'entartrage. Leur principal inconvénient est un manque de s…
A neural network to implement a hysteresis model for a magnetic material within a finite element program is described. It is shown that such a system can match the results produced by a Preisach model but the time overhead can be considerably reduced thus making feasible the solution of large problems involving hyster…
One factor responsible for the enhanced thermal stability of S-nitroso-N-acetylpenicillamine (SNAP), compared with S-nitroso-N-acetylcysteine (SNAC), has been shown, by ab initio calculations on model compounds, to be steric interactions in the dimerisation reaction leading to disulfide formation. Studies using DSC an…
A vector hysteresis model is experimentally tested for two soft magnetic materials in the two-dimensional case. The model expresses net magnetization as a sum of contributions from a number of pseudoparticles, each one having a dry friction-like hysteresis mechanism. Five adjustable parameters are used to represent hy…
The paper reports an experimental low-temperature study of the temperature-dependent behavior of the lattice constants, heat capacity, and thermal conductivity of the AlN ceramic. The results obtained are compared with the data available for the high-temperature region. The thermal expansion coefficient is found to be…
Quantum chemical calculations using the density functional theory were performed to model the mechanism of selective catalytic reduction of NO by NH3 on a supported vanadium oxide monolayer. In the first step, the adsorption of NH3 on a bimetallic cluster representative of vanadium oxide, containing a terminal V(DOUBL…
A twisted semi-hard magnetic wire of Vicalloy with composition of Fe/sub 41/Co/sub 48/V/sub 11/ revealed remarkable uniaxial magnetic anisotropy along central axis direction of the wire and showed a difference in coercivity between outer shell and inner core of the wire. Also the wire remained the large torsion stress…