Conjugated macrocycles. Part XXV. Cross-conjugated macrocycles with inner great rings of 16, 20, and 24 atoms
P. F. Clark, J. A. Elvidge and R. P. Linstead, J. Chem. Soc., 1954, 2490 DOI: 10.1039/JR9540002490
Materials Literature
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Paracyanogen: its formation and properties. Part I
L. L. Bircumshaw, F. M. Tayler and D. H. Whiffen, J. Chem. Soc., 1954, 931 DOI: 10.1039/JR9540000931
Anodic oxide films on tantalum electrodes
ANODIC OXIDE FILMS ON TANTALUM ELECTRODES PART 1. THICKNESS AND CURRENT EFFICIENCY OF FORMATION ANODIC OXIDE FILMS ON TANTALUM ELECTRODES PART 1. THICKNESS AND CURRENT EFFICIENCY OF FORMATION BY L. YOUNG Metallurgy Division, A.E.R.E., and Dept. of Chemistry, Imperial College Received 7th September,
The mechanism of inhibition of the corrosion of iron by solutions of sodium phosphate, borate, and carbonate
J. E. O. Mayne and J. W. Menter, J. Chem. Soc., 1954, 103 DOI: 10.1039/JR9540000103
Magnetic Resonance in Ferrimagnetics
It is shown that the general expression for the magnetic resonance frequency of the two-sublattice model of a ferrimagnetic crystal has essentially the same form as that originally obtained for the ferromagnetic case provided that the product of the molecular field coefficient and the net magnetization is large compar…
Antiferromagnetism
The familiar Heisenberg theory of ferromagnetism in the 3d transition metals iron, cobalt and nickel, rests on the assumption of a positive exchange integral between neighbouring ions, since ferromagnetism is not possible in cases where this integral is negative (` antiferromagnetic '). The idea that the remaining non…
3—THE EFFECT OF RATE OF EXTENSION ON THE TENSILE BEHAVIOUR OF VISCOSE AND ACETATE RAYONS, SILK AND NYLON
The essential features of two instruments for recording the load–extension curves of yarns at constant rates of extension from 0·001 to 1000 per cent per second are described. They were used to investigate the effect of the rate of extension on the tensile behaviour of viscose rayon (continuous filament, and staple fi…
Crystal Structure and Thermodynamic Studies on the Zirconium-Hydrogen Alloys
The phase diagram of zirconium‐hydrogen alloys was studied on alloys prepared at low temperature and for alloys in the composition range of to . Decomposition pressure studies were made over the composition range and for a series of temperatures. Results of these measurements were in complete agreement with crystal st…
Thermal Diffusivity of Metals at High Temperatures
A modified Ångström method for measuring thermal diffusivity and hence thermal conductivity of metals has been developed. Like previously reported dynamic methods, this method uses a heat source, whose temperature varies sinusoidally with time, located at one end of an effectively infinite rod. Unlike these methods, o…
Beitrag zur Kenntnis der Mangan(II)‐manganite und des δ‐MnO2
Abstract 1. A manganous manganite with a very low degree of disorder is described with the composition: 4 MnO 2 , Mn(OH) 2 , 2H 2 O. It is formed by recrystallisation of dry 3 MnO 2 , Mn(OH) 2 , xH 2 O, or in direct preparation by oxydation of Mn(OH) 2 with oxygen in alkaline solution. The X‐ray diffraction pattern ob…
Purine studies. Part II. The ultra-violet absorption spectra of some mono- and poly-substituted purines
S. F. Mason, J. Chem. Soc., 1954, 2071 DOI: 10.1039/JR9540002071
The excluded volume of branched chains
Abstract A theory of the excluded volume of branched molecules has been developed. The model of the branched molecule is a main or backbone string of beads from which side branches (which are themselves unbranched) originate. Each of these beads has the property of the Kuhn statistical chain element. The calculation i…
How to know the fresh-water algae; an illustrated key for identifying the more common fresh-water algae to genus, with hundreds of species named pictured and with numerous aids for their study
The phyla of freshwater algae herein recognized are as follows:
The thermal oxidation of hydrazine vapour
W. I. H. Winning, J. Chem. Soc., 1954, 926 DOI: 10.1039/JR9540000926
Glow-discharge electrolysis. Part II. The anodic oxidation of ferrous sulphate
A. Hickling and J. K. Linacre, J. Chem. Soc., 1954, 711 DOI: 10.1039/JR9540000711
Role of Sulfur in the Luminescence and Coloration of Some Aluminosilicates
Certain complex, sulfur‐containing sodalite‐type silicates, synthesis of which is described, exhibit under 3650 Å excitation an emission extending from 5000 Å to beyond 7000 Å, the spectrum varying with composition. The band structure of this emission at −196°C is similar to the emission structure shown by a mixture o…
TWO MULTICELLULAR MOTILE GREEN ALGAE,VOLVULINAPLAYFAIR ANDASTREPHOMENE, A NEW GENUS
This paper∗ deals with a new type of green alga originally found on the Cape Flats and since obtained in the United States of America and Australia. Initially identified as a second species of Volvulina Playfair, the considerations which led to the establishment of a distinct genus, Astrephomene, including the appeara…
Kinetics of the High Temperature Oxidation of Zirconium
The rate of oxidation of high purity zirconium was determined for the temperature range of 575° to 950°C at 1 atm pressure. Data can be fitted to a cubic law and the rate constant in (ml/cm 2 ) 3 /sec has been calculated to be , where 47,200 ± 1,000 cal/mole is the activation energy for the reaction.
30—The Torsional Rigidity of Textile Fibres
The initial resistance to twisting, or torsional rigidity, of single fibres from thirty-four samples has been measured by the torsion pendulum method, with period of oscillation from 4 to 9 seconds and twist less than half a turn per cm. Using preliminary experiments on the influence of tension, damping and period of…
The role of free radicals in the degradation of high polymers by ultrasonics and by high‐speed stirring
Abstract High molecular weight polymethacrylic acid in aqueous solution is rapidly broken down by ultrasonics (250 kc.). The rate of degradation varies as the shape of the molecule in solution is altered and is greatest when most asymmetric. It is concluded that cavitation is essential for the breakdown of the polymer…