Materials Literature
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The stability to light of 1,3,3,1′,3′,3′-hexamethyl-2,2′-indotricarbocyanine iodide (HITC) included in β-cyclodextrin (β-CyDx) has been examined. The quantum yield of the photodegradation of HITC was found to decrease with increasing formation of the inclusion complex, showing that the photostability of the dye can be…
Rare-earth manganese(III, IV) oxides REMn2O5 show a series of phase transitions at lower temperatures. There is a possibility that both electric and magnetic ordering coexist in a low-temperature phase. The recent dielectric, magnetic and magnetoelectric studies of these oxides are reviewed in this Paper.
The synthesis and crystal structure of the pseudo-orthorhombic (a≈b≈√2a0, c≈2a0) ordered perovskite MLaMgTeO6(M = Na and K) are reported. X-ray, electron and neutron diffraction and microscopy established that both compounds have a perovskite structure with ordering in the A and B sublattices.
Abstract The effect of tetraalkylammonium ions on the destabilization of foam has been studied by measuring the half‐life of foam (τ 1/2 ), area/molecule at the air/water interface, surface viscosity and critical micelle concentration (CMC) of sodium dodecyl sulfate (SDS). The area/molecule of SDS in organic salt solu…
The solvato- and halo-chromic behaviour of the phenolate dyes 4–6 is described and compared with their analogues 1 and 3. The observed trends are discussed and rationalized in terms of semiempirical molecular orbital calculations.
A facile synthesis of 2,3-disubstituted norbornadienes linked to meso-5,10,15,20-tetraphenylporphyrin ad anthracene by ethene or butadiene bridging groups is described and the potential of the derivatives to transport energy, a requirement for their action as molecular electronic devices, is discussed.
Abstract Cadmium Selenide (CdSe) thin films were prepared in different growth conditions by thermal evaporation. The films were characterised using transmission electron microscopy and X‐ray diffraction. The electrical parameters such as resistivity, carrier mobility, and concentration were determined. The sensitivity…
We demonstrate here the direct observation of the side view of surface folds in a swelling gel, which are induced by elastic instability. The fold structure along the thickness direction has been clarified, which is a prerequisite for understanding its singular nature. The elementary coarsening process of the fold pat…
The crystal of p-fluorophenyl nitronyl nitroxide [2-(4-fluorophenyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazol-1-oxyl 3-oxide, abbreviated as p-FPNN] radical has been found to possess a dimeric structure. Each dimer is related to adjacent ones by four-fold screw symmetry to form a three-dimensional network. The temp…
CuO/Al2O3 catalysts have been sulfated by oxidation of various amounts of SO2. The surface properties of the samples were studied using probe molecules. The IR spectra of CO species adsorbed on the non-sulfated sample show an strong band at 2125 cm–1 with a shoulder at 2160 cm–1, which shift to 2165 and 2180 cm–1, res…
A two-dimensional analysis of the in-plane misfit stress and its elastic relaxation in rectangular patterned heteroepitaxial SiGe/Si multilayer structures on Si substrate is presented. Based on the model of relaxing film stress the distribution of the misfit stress versus distance from the free surface of a multilayer…
Abstract 2‐(4′‐Hydroxyphenylbenzoyl)benzoic acid is readily available from phenolphthalein by reaction with hydroxylamine. On treatment with hydrazine, 4‐(4‐hydroxyphenyl)phthalazin‐1‐one is formed in high yield. Under conditions conventionally used for the synthesis of poly(aryl ether)s the phthalazinone reacts with…
The complex polymer [{Cu2L(pyca)(H2O}n][ClO4]n·2nH2O [H2L =N, N′-bis(2-ammoethyl)oxamide. Hpyca = pyridine-4-carboxylic acid] has been prepared and its magnetic properties and crystal structure determined. The crystals are monoclinic, space group P21/c, with 3 = 10.420(2), b= 13.118(2), c= 14.863(5)Å;, β= 93.05(2)°, a…
Diffusible hydrogen behavior in pre-strained high strength steel was investigated by use of a newly developed hydrogen content determining method for better understanding of delayed fracture.Pre-straining up to 4.2% formed a new hydrogen trapping site in the steel. When hydrogenerated in a 0.1N HCl solution, hydrogen…
The formation of h-BN by thermal decomposition of melamine diborate was examined by XRD, IR and thermal analysis. The melamine diborate, which was precipitated as white powders by cooling a hot solution of melamine and boric acid, was presumed to have a monoclinic structure with a=2.0259nm, b=1.4180nm, c=0.3504nm, β=9…
We establish the existence of isolated local minimisers to the problem of partitioning certain two-dimensional domains into three subdomains having least interfacial area. The solution we exhibit has the special property that the three boundaries of the minimising partition meet at a common point or “triple junction”.…
An ion-exchangeable layered perovskite compound, Na2La2Ti3O10, was directly synthesized by a solid-state reaction. The crystal structure of Na2La2Ti3O10 was determined by electron diffraction analysis and Rietveld analysis for the powder X-ray diffraction pattern. The unit cell is tetragonal with a=0.383528 (7) nm, c=…
In this report, controls of polymorphism and morphology of calcium carbonate compounds were studied by suspending amorphous calcium carbonate hydrate (ACC) powder in water or MgCl2 solution. Characteristics of calcium carbonate compounds formed from ACC were determined by means of X-ray diffraction, thermal analysis (…
The complexes [LnL2(NO3)2]NO3·nMeOH [L = 2,6-bis(benzimidazoi-2-yl)pyridme, Ln = Ce 1, n= 3; Ln = Eu 3 or Tb 4, n= 2] have been characterized by single-crystal X-ray diffraction, IR and 1H NMR spectroscopy and molar conductivity. They are ten-co-ordinate with six nitrogen atoms from two tridentate L ligands and four o…
Samples of Pt-10% Ir have been studied by X-ray photoelectron spectroscopy (XPS) to assess environmental contamination of reference kilogram masses. Samples were sputtered clean and distributed to four places where reference kilograms are kept at the NPL. All four specimens showed carbon and oxygen contamination which…