Materials Literature
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The signs of Vzz(and e2qQ) at the 57Fe nucleus for the following compounds have been measured by use of the Mössbauer magnetic field technique: trans-FeCl2(p-MeO·C6H4·NC)4, trans-FeCl2(depe)2[depe = 1,2-bis(diethylphosphino)ethane]. Na3[Fe(CN)5NH3],H2O, K3[Fe(CN)5H2O],7H2O, all positive; cis-FeCl2(p-MeO·C6H4·NC)4 and…
Crystals of [C5H12N]+2[As4S6]2– are orthorhombic, space group Imm2, with a= 10·25, b= 19·61, c= 5·97 Å, Z= 2. The anion possesses a ‘basket’ structure in which the four arsenic atoms, and two of the sulphur atoms, lie on crystallographic mirror planes; the bond lengths are: As–As 2·579(12), As–S(terminal) 2·183(10), A…
Abstract The fine structures of the highly crystalline cellulose microfibrils from the cell walls of the marine algae Valonia ventricosa, and the extra cellular chitin spines of the euryhaline diatoms Thalassiosira fluviatilis , have been investigated by observation of deformed and un‐deformed specimens in the electro…
The analysis of wavelength data of the Gd II spectrum has resulted in the detection of 108 odd and 70 even levels in addition to those reported by previous investigators. The total number of classified lines is now 2 200, belonging to 2 300 transitions between 162 odd and 150 even levels. The wavelength list, includin…
The far-i.r. spectra (40–700 cm–1) of some complex chlorides of general formula A2MCl4 and A3MCl5(A = Rb or Cs; M = Fe, Co, Ni, Cu, and Zn) which contain distorted MCl42– tetrahedra have been examined. The observed bands are assigned to internal modes of vibration associated with the MCl42– tetrahedra and to lattice m…
The potential of a number of silicates, of the felspathoid, fibrous clay, zeolite and other silicate groups, has been investigated for the trapping and storage of inert gases. The crystals, suitably outgassed, were exposed to high pressures of inert gas at high temperature and then quenched while still under pressure.…
The crystal and molecular structures of copper(II) hydrogen maleate tetrahydrate and copper(II) maleate hydrate have been determined by three-dimensional X-ray methods. In copper(II) hydrogen maleate (monoclinic, a= 3·594, b= 18·79, c= 9·69 Å, γ= 93·25°, space group l2/m, diffractometer data, R= 0·039) the copper atom…
Abstract The crystal and molecular structure of nickel(II)‐1, 8, 8, 13, 13‐pentamethyl‐5‐cyano‐ trans ‐corrin chloride has been determined by X‐ray analysis. The shape and dimensions of the corrin nucleus are discussed in some detail.
The compositions of thin films of pyrolytically deposited borosilicate glass were correlated with the infrared spectra of these films over the entire composition range. Although the composition has been related to the ratio, R , of the absorbance maximum at about 1300 cm −1 to the maximum at about 1050 cm −1 , the rel…
X‐ray analysis and electrical conductivity measurements (800°–1000°C) on yttria‐hafnia solid solutions between 2 and 20 m/o (mole per cent) Y 2 O 3 were made to locate the cubic phase and to select the composition best suited as a solid electrolyte. The phase boundary is located near 7 m/o Y 2 O 3 . Total conductiviti…
Abstract Proton NMR. spectra of purine, adenine, guanine and methylsubstituted guanines have been measured in CF 3 COOH, FSO 3 H and FSO 3 HSbF 5 SO 2 at 27° and low temperatures. These conditions permit to study multiple protonation of purines, using chemical shifts of CH, NH and OH protons. The spectra of mono‐, d…
Measurements of the heat capacity, thermal expansion, and thermal conductivity on synthetic crystals of undoped and neodymium-doped fluorapatite are reported. Fitting the low-temperature specific heat data to a Debye model yields a Debye temperature of 550°K. At 25°C the thermal expansion coefficients are 10.0×10−6 °K…
Measurements of thermal expansion and Young’s modulus at −150°∼500°C have been carried out with single crystal specimen, 3 mm in diameter and 12 cm long, of 18–12 type stainless steel. At the same time the rigidity modulus of a polycrystal specimen was measured at room temperature. At 20°C the Young’s moduli determine…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCrystal structures of americium trichloride hexahydrate and berkelium trichloride hexahydrateJohn H. Burns and Joseph Richard PetersonCite this: Inorg. Chem. 1971, 10, 1, 147–151Publication Date (Print):January 1, 1971Publication History Published online1 May 2002Published i…
The influence of chloride and sulfate ions on the corrosion of iron in H 2 SO 4 media at p H near 3 was studied. It was shown that both ions could be either aggressive or not aggressive under definite conditions. Chloride ions accelerate corrosion considerably when the anodic reaction contributes significantly to the…
The crystal structure of 8,12-diethyl-2,3,7,13,17,18-hexamethylcorrole has been elucidated by X-ray crystallographic analysis and the geometry of the macrocyclic ring system has been found to be not strictly planar. The distortions are probably caused by short N–N contacts brought on by the direct C(1)–C(19) link. The…
This review is concerned with the structure and resultant electrical conduction properties of three types of film, defined as metallic, dielectric and discontinuous metallic; it is shown that the behaviour of the last one can be discussed as extensions of the first two. The review commences with a brief discussion of…
Abstract Viscosity and pH of aqueous borate–poly(vinyl alcohol) mixtures were determined under different conditions toward a clarification of the thickening mechanism. Boric acid has little effect on dilute poly(vinyl alcohol) (PVOH), but sodium borate causes sharp viscosity increases which are temperature sensitive a…
Dimethylsilanone, Me2Si : O, is postulated as an intermediate in the gas-phase thermalde composition of octamethylcyclotetrasiloxane; a lower limit for the silicon–oxygen π-bond strength in dimethylsilanone is calculated.
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