Materials Literature
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The reaction of p-bromo(triisopropyloxysilyl)benzene 2 with magnesium led to stable THF solutions of the corresponding Grignard reagent. The reaction of this latter with PCl3 or PhPCl2 allowed the preparation of phosphines 4 and 5 respectively. LiAlH4 reduction of 4 afforded phosphine 6. Compounds 4 and 6 have been tr…
The oxidation of 1-(substituted phenylazo)-2-hydroxynaphthalene-6-sulfonate dyes by oxoiron(IV) tetra(2,6-dichloro-3-sulfonatophenyl)porphyrin (OFeIVTDCSPP) in aqueous solution is first-order in the concentration of the dye and of the oxoiron(IV) species over the pH range 6.93–12.68. The pH dependence of the second-or…
Fluoroalcohols [1,1,1,3,3,3-hexafluoropropan-2-ol (HFP), 2,2,2-trifluoroethanol (TFE) and 2-fluoroethanol (FE)], acting as Lewis acids, stabilize the π-conjugated, colored merocyanine forms of spiropyran and spirooxazine photochromic compounds as metal ions do.
Ab initio static electronic dipole hyperpolarizabilities, β(0), were computed for 1-(1‘,X‘-dicarba-closo-dodecaborane-1‘-yl)-closo-dodecaborane dianion (X = 2, 7, 12). These dianions have relatively large β(0) values (3.6 × 10-30 cm5 esu-1) comparable to those for 4-nitroaniline in spite of their short transition wave…
The interaction between haematite powder and formic acid has been studied at atmospheric pressure by FTIR and under high-vacuum conditions by X-ray photoelectron spectroscopy (XPS) and mass spectroscopy (MS). At room temperature formic acid is adsorbed mainly molecularly whereas dissociative chemisorption is prevalent…
A series of metalloporphyrin-containing cyclic hosts has been prepared, which are electronically and geometrically programmed to recognize guests in a particular configuration. Electronic control is achieved by substituting the C–H meso positions with carbonyl groups, while geometric control is possible in the choice…
119 Sn solid state nuclear magnetic resonance, 119Sn Mössbauer, Fourier transform Raman and variable temperature single crystal UV–VIS absorption, emission and excitation spectra of some archetypal microporous layered tin sulfides, denoted (Et4N)2Sn3S7 (TEA-SnS-1), (C6H12N2H)2Sn3S7 (DABCOH-SnS-1), (NH4)0.5(Et4N)1 .5Sn…
The crystal structure of the title compound was determined at 250 K in space group I 4 bar 2m, a = 20.661(5) Å , c = 6.764(7) Å , Z = 8. The individual dithiadiazole rings form two sets of contrarotatory 4-member pinwheels clustered around a 4-fold rotation-inversion axis located halfway along the unit cell edges, des…
This paper presents an experimental study on the manufacture of low-density fine-cell high density polyethylene (HDPE) foams in extrusion using CO 2 as a blowing agent. The strategies adopted to produce low-density, fine-cell HDPE foams were to generate a large number of cells by a rapid pressure drop, to suppress cel…
Rate coefficients for the depletion of ground-state nitrogen atoms by O 2 have been measured using a high-temperature photochemistry reactor. The N atoms were generated by VUV flash photolysis of N 2 O, and the relative concentrations were monitored by resonance fluorescence. The data are best fitted by the expression…
This paper deals with analysis by FEM for iron losses considering vector magnetic properties. We define the tensor magnetic reluctivity and calculate it from the data measured with two-dimensional measurement method. This numerical method is applied to the direct magnetic loss analysis. As a result, it is shown that t…
Abstract Oxalate is one of the dominant low molecular weight organic anions in many soils under forest ecosystems. Through its complexation reactions with Fe and Al, both in solution and at mineral surfaces, oxalate increases the availability of nutrients such as P in these soils. This investigation was designed to st…
Three new perylene-3,4-dicarboximide chromophores5a–c have been synthesized. They are characterized by high extinction coefficients and excellent thermal and photochemical stability. They display liquid crystallinity and exhibit several discotic phases depending upon temperature and substitution pattern.
The gas-phase reactions of molybdenum oxide cluster ions Mo x O y + ( x = 1−3, y = 1−9) with small alcohols have been investigated using Fourier transform ion cyclotron resonance mass spectrometry. The product branch ratios are reported. The reactions of Mo x O y + with alcohols can be envisioned as proceeding via met…
The non-hydrolytic sol–gel route has been used in the solvent-free synthesis of binary inorganic oxides based on silicon, aluminium and titanium. Where necessary, iron(iii) chloride was used as a catalyst. Clear evidence for the formation of true, amorphous binary systems was obtained only in the case of aluminosilica…
The ab initio determination of relatively complex crystal structures of flexible molecules without the need for single crystals is discussed. A method is described based on simulated annealing in which the powder diffraction patterns of randomly generated trial structures are calculated and compared with the observed…
Time-resolved in situ Raman spectroscopy was used to follow the decomposition of supported crystalline BaO 2 into defect-rich BaO. This decomposition occurred under O 2 partial pressures which were small compared to those expected from a calculated phase diagram. However, the O 2 partial pressures at which this BaO 2…
Different crystal forms of ibuprofen (IBF) were prepared using methods such as cooling hot solution of the drug and precipitation of crystals from the drug solution. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), melting point, x-ray powder diffractometry, infrared absorption spectroscopy…
The europium(II)-doped aluminates, SrAl2O4 and CaAl2O4with β-tridymite structure and BaMgAl10O17 with β-Al2O4 structure, have been investigated by means of EPR spectroscopy. From the complicated X-band EPR spectra observed for SrAl2O4:Eu,Dy and CaAl2O4:Eu,Nd it is deduced that they have large zero-field splittings in…
A rhenium(I) complex with boronic acid pendant is synthesized and characterized; the complex is shown to exhibit pH dependent electronic absorption characteristics; the photophysical properties and sugar sensing behaviour are also investigated.