Vibrational spectrum of trimethylsulfonium bromide
Abstract Trimethylsulfonium bromide (CH 3 ) 3 SBr has been prepared; melting range 183‐186°C. Infrared absorption and Raman spectra have been recorded and assigned.
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Studies of the charge-transfer complexes of 1,4-naphthoquinone acceptors
The naphthoquinone acceptors form stable charge-transfer complexes in solutions of aprotic solvents with aromatic hydrocarbons as donors. From the charge-transfer transition energies of the complexes as well as from the polarographic half-wave reduction potentials of the acceptors relative electron affinities of the a…
Thermal Stresses of the Elastic Plane with a Circular Hole, Including One Heat Source
The thermo-elastic solutions for the case of one heat source near a circular hole in an infinite elastic plate are given in the steady-state condition using the thermal expansion displacement for "zero stresses". It is assumed that the temperature along the edge of this hole is held at zero degree always. Numerical ca…
Polycyclic fluoroaromatic compounds. Part V. Some reactions of 1,2,3,4-tetrafluoronaphthalene
1,2,3,4-Tetrafluoronaphthalene undergoes nucleophilic and electrophilic substitutions in the fluorocarbon and in the hydrocarbon ring respectively. On treatment with sodium methoxide, hydrazine, and lithium aluminium hydride, the 2-fluorine atom is displaced predominantly. Bromination and nitration yield mixtures of c…
Factors Affecting the Growth Rate of Plasma A nodi zed Al[sub 2]O[sub 3]
This paper discusses the affects of anodization parameters on the growth rate of plasma anodized . Variations in growth rate were inferred by observing the variations in the anodic current decay while anodizing at a constant bias potential. The following effects have been observed: (a) Sputtered cathode oxide was foun…
Solid-state vibrational spectroscopy. Part II. The vibrational spectra of some chromates and dichromates
The solid-state (powder) i.r. (1000–40 cm–1) and Raman (1000–130 cm–1) spectra of sodium, potassium, and ammonium chromate(VI) and dichromate(VI) are reported and compared with the previously reported solution Raman spectra. Considerable splittings of the degenerate modes are observed and an attempt is made to account…
Linear Sweep Voltammetry of Ni(II), Co(II), Cd(II), and Pb(II) at Glassy Carbon Electrodes in Molten Lithium Chloride-Potassium Chloride Eutectic
The reduction of Ni(II), Co(II), Cd(II), and Pb(II) was studied at glassy carbon electrodes in molten lithium chloride‐potassium chloride eutectic at 450°C using the technique of linear sweep voltammetry. Peak‐shaped voltammograms were obtained at scan rates of 10 mV to 1 V / sec . Linear dependence of peak currents o…
Infrared and Mössbauer spectra of tetracarbonylcadmioiron and related complexes
The i.r. and Mössbauer spetra of CdFe(CO)4 and of several complexes of the type L2MFe(CO)4(M = Zn or Cd; L = nitrogen donor ligand) have been recorded. The Mössbauer spectra indicate the presence of octahedrally co-ordinated iron atoms and, on this basis, possible structures for the complexes are discussed. The comple…
Redetermination of the crystal structure of [NH4]2[SbCl5]
The structure of the title compound has been redetermined from three-dimensional X-ray data and shown to be in good agreement with the previous study. The structure consists of ammonium ions and approximately square pyramidal [SbCl5]2– ions with antimony–chlorine distances of 2·36, 2·58 (two) and 2·69 (two)Å.
Oxidative reactions of cellulose initiated by free radicals
Abstract Oxidative reactions in cellulose are commonly initiated by thermal, ultraviolet, and high‐energy radiations and by chemical oxidation. Long‐lived free radicals, formed in cellulose on the localization of energy from thermal, ultraviolet, and high‐energy radiations, and short‐lived free radicals, formed in cel…
Optical Spectrum of Triply Ionized Erbium in Calcium Tungstate
The energy levels of the I4 ground term of Er3+ in single crystals of CaWO4 were established by absorption and fluorescence spectra measurements. The measurements were made using crystals at temperatures of 2, 20, and 85°K. The energy level scheme allows an interpretation of the 1.612-μ four-level CaWO4:Er3+ laser tra…
Predicting storage stability from time-temperature data
Methods are given to assist in choosing an appropriate equation relating product quality to storage time and temp. and for determining the constants of the equation. Figures prepared from these equations show contours of constant product quality as related to time and temp. From the plotted contours, storage condition…
Phase Equilibria in the Sr[sub 3](PO[sub 4])[sub 2]-Cd[sub 3](PO[sub 4])[sub 2] System and Eu2+-Activated Luminescence of Sr[sub 3](PO[sub 4])[sub 2] and Related Phases
The phase equilibria relationships in the Sr 3 ( PO 4 ) 2 ‐ Cd 3 ( PO 4 ) 2 system were established in air using DTA and melting point data obtained from compositions previously equilibrated by solid‐state reactions. In addition to the previously reported rapid, reversible α ⇄ β ‐ Sr 3 ( PO 4 ) 2 polymorphic inversion…
Heats of immersion of pure and doped magnesia in cyclohexane. Effects of micropores
Heats of immersion of pure and doped magnesia in cyclohexane were measured at 35°C for samples heated at different temperatures in vacuo. For the pure samples, rise in temperature of thermal treatment leads to a gradual decrease in the heats of immersion normalized per unit area (h1, ergs cm–2), till a certain limitin…
The sign of the 57Fe quadrupole splittings in iron(II) low-spin compounds: partial quadrupole splittings and bonding properties of ligands
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…
Crystal structure of piperidinium hexathiotetra-arsenate
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…
The substructure of crystalline cellulose and chitin microfibrils
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 the spark spectrum of gadolinium (Gd II)
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…
Far-infrared spectra and single-crystal reflectance spectra of some complex chlorides containing distorted MCl4 2? tetrahedra
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…
Trapping and diffusion of rare gases in phillipsite, zeolite K—M and other silicates
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.…