bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phenol‐formaldehyde and allied resins. V.—Synthesis of a bridged decanuclear novolak and a case of hardening by way of meta‐substitution
Authors: Hunter R. F. , Turner C. 
Published: July 2010

AbstractThe bridged decanuclear novolak (V) has been synthesized rationally as a non‐crystalline chemical individual from 2: 6‐bis‐2′‐hydroxy‐5′‐methylbenzyl‐4‐bromophenol (I) by way of the dimethylol derivative (II) which on reaction with 2: 4‐xylenol furnished 2: 6‐bis‐2′‐hydroxy‐3′‐(2″‐hydroxy‐3″: 5″‐dimethylbenzyl)‐5′‐methylbenzyl‐4‐bromophenol (III) which was debrominated to the pentanuclear novolak (IV). On reaction with an equivalent of formaldehyde in acetic acid, using sulphuric acid as catalyst, the latter gave the required bridged decanuclear novolak (V). In the presence of excess of acid formaldehyde, both the pentanuclear and the decanuclear novolaks were readily converted into hardened products whose infra‐red absorption spectra indicated the formation of methylene bridges in meta‐position to the hydroxyl groups.
Adsorption of aldehydes and ketones on anion exchangers in cyanide form
Authors: Gabrielson Gunnar 
Published: July 2010

AbstractOf seven common aldehydes examined on cyanide‐treated Dowex‐2 columns, vanillin, salicylaldehyde, benzaldehyde and crotonaldehyde were more or less completely adsorbed and were eluted with water to only very small extents; furfural was completely recoverable and formaldehyde and acetaldehyde partially so. There was some indication of polymerization of some of the aldehydes on the column.Acetone and ethyl methyl ketone were very easily eluted with water from these columns.
Ternary vapour‐liquid equilibria system: Acetoneethyl methyl ketone‐cyclohexane
Authors: Rao K. V. Kurmanadha , Krishnamurty V. V. G. , Rao C. Venkata 
Published: July 2010

AbstractExperimental T‐x‐y data of the system: acetone‐ethyl methyl ketone‐cyclohexane at 760 mm. Hg pressure are reported. The data were obtained using a modified Colburn type of equilibrium still. No ternary azeotrope was observed.The experimental data were found to be thermodynamically consistent according to the method of Krishnamurty & Venkata Rao which is based on the Gibbs‐Duhem equation.The activity coefficient data of the present system have been satisfactorily correlated with the modified Margules equations developed earlier, using a ternary constant Ct = 0·5. In the case of the present system, the modified Margules equations with Ct = 0·5 are equivalent to the three‐suffix ternary Margules equations of Wohl, with C = 0·305. The ternary smoothed experimental T‐x‐y data are compared with the data calculated using the modified Margules equations with Ct = 0·5 and there is close agreement between the calculated and experimental data.It is suggested that the thermodynamic consistency test proposed by Krishnamurty & Venkata Rao and the modified Margules equations may be used together for mathematical analysis of the ternary vapour‐liquid equilibrium data since the same smoothed experimental log γi/γj values can be used for both the methods.
The determination of naphthalene in town gas by the picrate method. II. The indene correction
Authors: Mott R. A. , Moulson I. 
Published: July 2010

AbstractThe conventional method of determining the picrates formed by the unsaturated hydrocarbons such as indene is the use of an aliquot of the solution of the recovered picrates in chloroform, another aliquot being used for the determination of the total picrates. The accuracy of these determinations is enhanced by the use, for each, of the total quantity of recovered picrates: this is facilitated by the use of acetone as the solvent and bromothymol blue as the indicator in the titration of the total picrates. Errors in the determination of the indene are minimized by using suitable excesses of acetic acid and Wij's solution and keeping for 20 min. before titrating the unused iodine with standard sodium thiosulphate solution.
Studies on glyceryl esters. I. The formation of urea inclusion compounds with 1‐monoglycerides
Authors: Aylward F. , Wood P. D. S. 
Published: July 2010

AbstractThe 1‐monoglycerides of saturated even fatty acids from caprylic to stearic have been shown to form inclusion compounds with urea. The preparation of pure adducts and the crystal size and form of the various members of the series have been described, and the molecular ratios of urea to lipid, and also the ‘dissociation’ and ‘exudation’ temperatures have been determined.
The determination of the cement content of soil–cement. III An investigation of some of the factors involved
Authors: Sherwood P. T. 
Published: July 2010

AbstractIn the two previous parts of this paper a method was described for determining the cement content of a soil–cement mixture by measuring the calcium oxide contents of the soil, the cement and the mixture. Since this earlier work, alternative methods have been developed for estimating calcium, and in the present investigation these have been applied to the measurement of cement content. A series of comparisons has been made between the different methods, and that using ethylenediaminetetra‐acetic acid has been found to be most satisfactory.The effect of the sampling procedure on the accuracy of the analyses has also been studied, and recommendations are made regarding sampling technique.
Measurement of the specific surface area of fine powders. A comparison of the ‘gas‐adsorption’ and ‘air‐permeability’ methods
Authors: Mathews D. H. 
Published: July 2010

AbstractMeasurements of specific surface areas of nineteen powders of various chemical and physical types have been made (a) by adsorption of nitrogen on to the powders at 77° K and (b) by the air‐permeability method described by Rigden.The results obtained by the two methods were appreciably different, the areas obtained by the adsorption method being in all cases the larger. It is suggested that the discrepancy between the two sets of measurements may be due in part to the existence of an internal surface in some of the powders, which was not measured by the air‐permeability method.
The determination of lead in polyvinyl chloride compositions containing lead stabilizers
Authors: Grossman S. , Haslam J. 
Published: July 2010

AbstractA rapid method has been devised for the determination of lead in lead‐filled polyvinyl chloride compositions. The polymer is dissolved in ethylene dichloride and the lead extracted with strong hydrochloric acid solution. This hydrochloric acid solution is separated and diluted to 50% v/v strength with water prior to the determination of the lead by measurement of the u.v. absorption of the lead chloride complex at 270 mμ. A slight modification of the method avoids the interference of iron compounds which may be present in a composition.
The study of slag‐metal mixing efficiency by models
Authors: Shanahan C. E. A. , Cooke F. 
Published: July 2010

AbstractThe relative efficiencies of various methods of mixing liquid slag and metal have been studied by means of cold models. Using sodium amalgam as ‘metal’ and dilute sulphuric acid as ‘slag’ it has been shown that a most efficient method of mixing consists of pouring the metal into the slag and that the degree of mixing is dependent on both the drop height and the rate of pouring.Mixing by means of blowing gas through a single jet into the system and by rabbling is much less intense, whilst a simple model converter gave mixing efficiencies comparable with those obtained by pouring at low flow rates.Some preliminary experiments have been carried out using a model system consisting of n‐hexane and an aqueous solution of zinc chloride, methyl red being used as the transfer agent. This system should facilitate work on the correlation of the cold model with full‐scale plant.
Ternary liquid equilibria. IV. Various systems
Authors: Rao M. Raja , Rao C. Venkata 
Published: July 2010

AbstractPhase equilibrium data are presented for the ternary liquid systems, namely, acetic acid‐water‐hexane, ethylene glycol‐water‐n‐butanol, ethylene glycol‐water‐ethyl methyl ketone, and ethyl methyl ketone‐water‐cyclohexane. The tie‐line data for all the systems have been analysed by the methods of correlation of Othmer & Tobias and Hand, and fitted reasonably with the respective plots. For the system acetic acid‐water‐hexane, the tie‐lines, when produced beyond the binodal curve, meet at a point on the extended base line of the ternary equilibrium diagram and this facilitates the interpolation and extrapolation of the tie‐line data. A comparison of the present data for glycol‐water systems with the literature data for the corresponding systems containing n‐pentanol and n‐hexanol respectively as solvents, has confirmed earlier conclusions, namely, that for any solute‐water combination, when the solvent is changed in a homologous series in the order of increasing molecular weight, the area of heterogeneity increases, and the solute favours the aqueous phase more and more.
Gas‐liquid chromatography. I. Retention‐volume data of certain tar acids
Authors: Irvine L. , Mitchell T. J. 
Published: July 2010

AbstractThe corrected retention volumes per gram of stationary phase (Vg) are given for thirty tar acids at 183°, 155° and 135°. The results were obtained from a 4‐ft. column using Apiezon‐L stopcock grease as stationary phase and Celite‐535 as mechanical support. The carrier gas was nitrogen and thermal conductivity was used for detection of constituents.
Investigations into the electrodeposition of titanium metal from titanium tetrachloride in fused alkali metal chloride systems
Authors: Burgess J. , Brown G. T. , Roberts C. W. 
Published: July 2010

AbstractAn account is presented of work carried out on the single‐stage, electrolytic reduction of TiCl4 to titanium metal. Emphasis is placed on metal quality as determined by hardness values, and the effects of a number of experimental variables have been studied both on hardness and on current efficiency and yield. In several cases, a minimum hardness level of 300–350 D.P.N. on melted metal was achieved, and it was shown to be possible to prepare titanium metal of this quality at high current efficiency and yield. The use of porous diaphragms in the cell, whilst necessary for high efficiencies, resulted in an irregular contamination of the metal throughout any one experiment, although not affecting the minimum hardness obtained. The deposited metal was, in all cases, of small particle size and generally dendritic in structure.
The relationship between magnesium content and stress‐corrosion susceptibility of aluminium‐magnesium alloys
Authors: Vance W. J. 
Published: July 2010

AbstractThe susceptibility to stress‐corrosion cracking of commercial purity aluminium‐3.5% magnesium and aluminium‐2.25% magnesium (nominal) alloys has been determined by corroding strain‐aged 16 s.w.g. wire specimens by intermittent immersion in buffered 3% sodium chloride solution. Susceptibility values for the 3.5%‐Mg and 2.25%‐Mg alloys were 18.4% and 0% respectively.Comparison with the stress‐corrosion susceptibility values reported by Jones1 on aluminium‐7% magnesium and aluminium‐5% magnesium alloys suggests that susceptibility is proportional to alloying magnesium content within the range of alloys examined by this method.
Electrodialysis using ion‐exchange membranes. I. Factors limiting the degree of desalting
Authors: Partridge S. M. , Peers A. M. 
Published: July 2010

AbstractThe behaviour of potassium chloride solutions in a continuously operated electrodialysis cell using ion‐exchange membranes is described. The cell contained 25 desalting compartments and 25 concentrating compartments each 1.58 mm. thick. The membranes were supported by perforated separators carrying grooves for the passage of liquid, and turbulent flow was induced by forced recirculation. The dependence of current efficiency on the ion concentration in the desalting compartments was assessed and the effect of a number of design factors was investigated. Theoretical expressions have been derived for the current efficiency of the desalting process.
A pilot plant for the continuous culture of micro‐organisms
Authors: Harrison R. W. 
Published: July 2010

AbstractThe continuous‐culture pilot plant at Clevedon is based on Monod's large bactogen. The special feature of this type of apparatus is the rotating drum inside the fermenter which insures good aeration and mixing without the incorporation of a sparger. The apparatus is designed for the cultivation of non‐pathogens only.
Phosphoric acid treatments for steel. I. The nature of coatings produced by the action of phosphoric acid on steel
Authors: Donovan M. , Scott J. W. , Shreir L. L. 
Published: July 2010

AbstractThe nature of the mixed phosphates present in coatings produced by the action of phosphoric acid on a clean steel surface has been investigated. It has been shown that the coating composition changes with time of exposure to atmospheric oxygen. The role of oxygen in the reaction mechanism is discussed.
Electrode potential studies on iron in dilute phosphate‐chromate solutions
Authors: Ride R. N. 
Published: July 2010

AbstractThe electrode potential behaviour of iron in aerated potassium phosphate solutions (2500 p.p.m.) is reproducible at pH 5·2 and 6·1, major breakdown and removal of the pre‐immersion oxide film being followed by slow, uniform corrosion. When potassium dichromate (30 p.p.m.) is subsequently added, the potential rises logarithmically from a critical, pH‐dependent value and re‐passivation is achieved through the growth of a new oxide layer. In chromate‐free solutions, re‐passivation due to dissolved oxygen alone is a much slower process.The potential behaviour is not reproducible in solutions which contain both phosphate and chromate from the start. Generally, the pre‐immersion oxide is not removed but the maintenance of the passive state is unpredictable since it depends on the capacity of the inhibitive system to block effectively the sporadic pores in the film with precipitated hydroxide.The significance of potential values has been examined in relation to the pH—potential equilibrium data for the iron‐water system. Reasonable agreement between breakdown potentials and theoretical values has been observed.
Polymers from oxacyclobutanes II. The laboratory‐scale evaluation of the polymer from 3: 3‐bischloromethyloxacyclobutane
Authors: Sandiford D. J. H. 
Published: July 2010

AbstractThe physical and mechanical properties of the polymer under various temperature conditions are studied in detail. The product has electrical properties very similar to those of polyethylene terephthalate and is mechanically intermediate between polythene and nylon.
Note on the characteristics of potential‐time curves for painted non‐ferrous metals
Authors: Greenblatt J. H. 
Published: July 2010

AbstractThe potentials of steel, aluminum, brass and copper rods overcoated with various paints were measured in sea‐water over a period of time. The potentials obtained in all cases were determined by the substrate metal rather than the paint coating used. It is concluded that essentially one is measuring the potential of bare local anodes. The potential‐time curves on copper, brass and aluminum have the same characteristics as those on steel.
The measurement and mechanism of oxygen transfer in submerged culture
Authors: Solomons G. L. , Perkin M. Patricia 
Published: July 2010

AbstractA comparison of the sulphite oxidation and polarographic methods of determining oxygen‐transfer rates has been made. It has been found that the former behaves as a gas‐film‐, and the latter a liquid‐film‐controlled process. A start has been made on a rational approach to scale‐up of fermenters, based on the mass‐transfer rate and degree of turbulence. The effects of mould mycelium, anti‐foam and of surface‐active agents are discussed.
The selective absorption of hydrogen sulphide in carbonate solutions
Authors: Garner F. H. , Long R. , Pennell A. 
Published: July 2010

AbstractA study of both a wetted‐disc and a wetted‐wall column has indicated that the latter is the more suitable for obtaining mass‐transfer data in spite of the tendency to ripple formation.A study has been made of the absorption of hydrogen sulphide and carbon dioxide from a gas mixture with a CO2 H2S ratio of 30: 1 in solutions of sodium and potassium carbonates.Selectivity for the absorption of hydrogen sulphide has been found to decrease with increase in wetting rate and with increase in temperature. It increases with increase in gas rate and increases slightly with increase in concentration of sodium carbonate in the solution above about 1·1–1·3‐N. The concentration of hydrogen sulphide in the gas has no effect on the selectivity provided it is more than 1·3% but below this concentration, the selectivity decreases as the concentration decreases.The gas film conditions are more important than those in the liquid film for hydrogen sulphide concentrations in the gas of about 1%. The absorption of carbon dioxide is independent of gas film conditions and is controlled by the rate of a slow reaction in the liquid film.The practical absorption conditions required to secure maximum removal of hydrogen sulphide and minimum removal of carbon dioxide are listed.
The anomalous behaviour of carbonate in phosphate rock
Authors: Feilchenfeld H. , Eden C. 
Published: July 2010

AbstractIsrael phosphate‐bearing rock is shown to contain in addition to calcite another form of carbonate, which dissociates irreversibly below the dissociation temperature of calcite. The phenomenon can be explained on the assumption that the calcium oxide produced on dissociation of the second form becomes an integral part of the apatite lattice. It is therefore plausible to suggest that the second form is either finely dispersed throughout the apatite or itself constitutes part of the apatite lattice.
The crystalline arrangement in fusion‐cast cylinders of 2: 4: 6‐trinitrotoluene and its relationship to colour, density and behaviour on detonation
Authors: Williamson W. O. 
Published: July 2010

AbstractMelted 2: 4: 6‐trinitrotoluene crystallized as an orthorhombic modification elongated on [c] and flattened on {010}. These characteristics allowed the arrangement of the crystals in fusioncast cylinders to be ascertained by use of the polarizing microscope in conjunction with novel techniques which are described. The arrangement could be varied by allowing uninterrupted cooling or by stirring or ‘seeding’ etc. The cylinders containing the coarsest crystals tended to be the least dense, the least sensitive to detonation and the most prone to unstable detonation. This was shown by Cybulski et al.1 whose castings were among those examined.Uninterrupted cooling in a hollow metallic cylinder favoured a radial disposition of crystals elongated on [c] except at the base of the cylinder where such elongation was axial over a limited length. The colour by incident light of the casting, or of sections cut therefrom, depended on (1) the presence of impurities in the crystals, (2) superficial irreversible darkening due to illumination and (3) an optical effect caused by the aggregates of parallel crystals. Such aggregates transmitted more incident light in the direction of parallelism than at right angles thereto; thus the flat surfaces of vertically bisected cylinders with radial crystallization showed dark median streaks not dependent on the segregation of impurities during crystallization.The peculiarities of crystalline arrangement near the mould surface are described but a true ‘chilled margin’ was not identifiable by the present techniques.
Action of chlorine trifluoride on trichloroacetic acid
Authors: Cuthbertson F. , Holmes T. F. , Musgrave W. K. R. , Tanner M. C. 
Published: July 2010

AbstractTrichloroacetic acid is rapidly decomposed by chlorine trifluoride with the formation of carbon dioxide, carbonyl halides, carbon tetrachloride, chlorofluoromethanes, and hexachloroethane. There is no evidence for the replacement of chlorine atoms by fluorine before decarboxylation.
The reaction of alkaline hydrogen peroxide with certain acid halides and anhydrides in the presence of benzidine‐type bases
Authors: Marsh D. J. , Neale E. 
Published: July 2010

AbstractA study has been made of the colour‐forming reaction between alkaline hydrogen peroxide and certain acid halides and anhydrides in the presence of benzidine‐type bases, which has formed the basis of a colorimetric method for the estimation of phosphonofluoridates and related compounds. The scope of the reaction is indicated, and suggestions are made with regard to its mechanism and the nature of the coloured product.
Preparation of ‘high‐ortho’ novolak resins. III. The use of substituted phenols
Authors: Fraser D. A. , Hall R. W. , Raum A. L. J. 
Published: July 2010

AbstractThe condensation of some substituted phenols with formaldehyde in the presence of ions of electropositive bivalent metals is described. m‐Cresol formaldehyde and m‐ethylphenol/formaldehyde novolaks produced with these catalysts have a shorter cure time than those formed under conditions of acid catalysis. Resins from 3: 5‐xylenol and m‐isopropylphenol do not show this effect.Certain discresylmethane isomers formed in the condensation of m‐cresol with formaldehyde have been isolated, purified and identified. The reactivities of novolaks formed by the condensation of these isomers with formaldehyde have been measured and resins from o‐o' isomers found to have the fastest rates of cure with hexamine.
The Reaction of nitric acid with formaldehyde and with formic acid and its application to the removal of nitric acid from mixtures
Authors: Healy T. V. 
Published: July 2010

AbstractEfficient methods are given for decreasing or eliminating the nitric acid content of solutions of inorganic nitrates with recovery of oxides of nitrogen and leaving behind no added reagent.The reaction of both formaldehyde and formic acid with nitric acid (2–20N) has been studied at 100°. At constant concentrations of formaldehyde and formic acid the reactions are of apparent third‐order over the nitric acid range 2–15N (rate constants given).Further reaction of formaldehyde or formic acid with nitrate solutions causes precipitation of metal hydroxides as the pH of the solution rises; this may be used as a basis of separation of metals from solution. Nitrates can be converted to other salts such as chloride or sulphate by reaction with formaldehyde after addition of the appropriate acid.Nitrites do not react with formaldehyde in neutral solution, but nitrous acid, liberated by hot acid, decomposes partially into nitric acid which then reacts with formaldehyde as above.
The surface properties of precipitated alumina. 111. Samples prepared from aluminiumisopropoxide
Authors: Harris M. R. , Sing K. S. W. 
Published: July 2010

AbstractSamples of precipitated alumina were prepared by the hydrolysis of aluminium isopropoxide, both under homogeneous and heterogeneous conditions. Nitrogen adsorption isotherms were determined on the samples at −196°. after storage and outgassing at room temperature. Surface areas were calculated from the isotherms by the standard Brunauer, Emmett & Teller (B.E.T.) method.The adsorption isotherms were of the type given by porous solids and resembled those obtained ‘activated’ alumina rather than on the alumina prepared previously from aluminium chloride solution. A range of high surface areas were found, the homogeneous precipitate having a particularly large initial area and pore volume. Some ageing occurred but it dld not cause the area to below 300 m.2g.−1The water content remaining in the samples after outgassing did not correspond to the composition of a well defined hydrate.