bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oxidation of boart
Authors: Young R. S. , Benffield D. A. 
Published: July 2010

AbstractStudies have been carried out on the rate of oxidation of different types and sizes of boart at various temperatures. For each variety and particle size of boart there is a ‘critical temperature’ above which losses increase rapidly even for such short heating periods as five minutes.Oxidation of boart is markedly decreased by the proximity of certain substances such as tungsten carbide, tungsten, cobalt and graphite. Natural impurities in boart have a similar, protective action on oxidation and loss of diamond. As the particle size decreases, all cleaned boarts tend to become similar in composition and consequently possess similar reactions towards heat treatments.
Wool wax. ii. Lime saponification
Authors: Rossouw S. D. , von Rudloff E. 
Published: July 2010

AbstractMethods for the saponification of wool wax are discussed. The rate of saponification of wool wax with lime has been investigated and the effects of certain additives on the rate have been studied. From the results optimum conditions have been chosen. On applying these on a 1‐kg. scale, complete saponification was obtained at 140° in six hours. Separation of the product into calcium soaps and non‐saponifiables was effected by acetone extraction.
Low‐temperature production of oxidized oil gels
Authors: Walker F. T. , MacKay T. 
Published: July 2010

AbstractLarge quantities of drying oil, mainly linseed, oxidized at low temperatures (below 90°) are consumed in the manufacture of linoleum. The two main processes of oxidizing the oil, the scrim and the mechanical, are reviewed. It is shown that the rate of oxidation obtainable at any temperature increases in direct proportion to the air/oil interface. A new process is described, in which the oxidation apparatus is a randomly packed column wherein a constantly flowing thin film of oil passing down is oxidized by a counter‐current stream of hot air. This method appears to combine some of the merits of both the scrim and the mechanical process.
The addition of thio‐compounds to olefins. III. Reactions of tri‐ and hexa‐methylenedithiols, and of bisthiol‐adipic and ‐sebacic acids
Authors: Cunneen J. I. 
Published: July 2010

AbstractCertain dithiols and bisthiol‐acids react with natural rubber and with some related simple olefins in an analogous manner to the corresponding monofunctional compounds. The physical characteristics of the vulcanizates obtained from natural rubber and bisthioladipic acid are described.
The determination of sulphur, sulphide, thiosulphate, sulphite and sulphate in commercial calcium chloride
Authors: Fogg D. N. , Wilkinson N. T. 
Published: July 2010

AbstractMethods have been developed for the determination of sulphur, sulphide, thiosulphate, sulphite and sulphate when present together in commercial calcium chloride.The analysis is divided into three sections:Section I.—Precipitation of sulphide by addition of zinc carbonate suspension; the precipitate also contains all the elementary sulphur present in the sample, and some insoluble sulphite and sulphate. The filtrate contains soluble thiosulphate, sulphite and sulphate, and these are determined by well‐known methods.The zinc carbonate precipitate is examined for sulphide and insoluble sulphite by iodine titration. The precipitate from another zinc carbonate separation is added to an excess of acidified iodine solution in which case sulphur is precipitated in amount equivalent to the sulphide present. This sulphur is separated together with any sulphur present in the sample, oxidized to sulphate and determined as barium sulphate. The filtrate from the acidified iodine separation of sulphur contains sulphate equivalent to the insoluble sulphate and sulphite associated with the zinc carbonate separation.Section 2.—Total sulphate is determined in the sample by first boiling with dilute hydrochloric acid and then precipitating the sulphate with barium chloride.Section 3.—A third portion of the sample is used for the determination of insoluble sulphite plus total sulphide.A separation of the insoluble sulphite and sulphide is carried out with zinc carbonate suspension and the mixture filtered. The sulphide together with insoluble sulphite is determined in the precipitate by titration with iodine. The filtrate contains soluble sulphate, sulphite and thiosulphate.From the results of analyses of each section and by a series of calculations the contents of sulphur, sulphide, thiosulphate, sulphite and sulphate can be obtained.The scheme of analysis is shown on p. 367.
The distribution of alcohols in the products of the fischer‐tropsch synthesis
Authors: Gall D. , Gibson E. J. , Hall C. C. 
Published: July 2010

AbstractAn alcohol‐rich product obtained by Fischer‐Tropsch synthesis at 160–175° and 150 lb./sq. in. (gauge), in the presence of a cobalt catalyst has been examined. It was found that n‐primary alcohols constituted 40% by weight of the organic liquid products (oil, spirit and organic matter in the water) and 92·4% of the total oxygenated products. The proportions of acids and carbonyl compounds were, therefore, markedly lower than those reported to be present in an iron‐catalyst product of the Hydrocol type.The proportion of methanol present was very low, ethanol was present in the largest proportion and the proportions of the alcohols higher than propanol decreased with increasing carbon number. The proportion of propanol was less than that of butanol or pentanol so that the carbon‐number distribution curve for the alcohols showed a marked inflexion in the C3‐C4 region, which is not shown by the published distribution curve for the alcohols in the Hydrocol product.From a study of the relative rates of decomposition of a series of n‐primary alcohols at 150° in the presence of hydrogen and a cobalt catalyst, it was possible to plot a curve relating alcohol stability and carbon number. This curve resembled the distribution curve in showing a low value for C1, a maximum at C2 and a marked inflexion in the C3‐C4 region, suggesting that the individual alcohols are present in the products of synthesis in proportions which are determined, at least in part, by their relative stabilities under the synthesis conditions.It is considered that the alcohol distribution curve is of a form which would be predicted if the mechanism of alcohol formation involved step‐wise addition of methylene radicals to one end of a growing chain terminated by a hydroxymethylene radical, and if the survival of the alcohols was controlled by their relative stabilities.From a consideration of the observed results and of those reported by other workers in the field, it is concluded that there is a balance of evidence in favour of the view that alcohols are the precursors of hydrocarbons in the synthesis.
Enzymes from micro‐fungi
Authors: Dingle J. , Solomons G. L. 
Published: July 2010

AbstractOne hundred and thirteen cultures of micro‐fungi were grown in both surface and submerged conditions and were then examined for production of polygalacturonase, α‐amylase, protease, cellulase (Cx) and lipase. Surface cultures were grown using the micro‐cylinder technique, and submerged cultures by the roll‐tube method.This survey was carried out in order to find fungi that could produce enzymes for industrial use.
The mixing of casein glues
Authors: Lacey P. M. C. 
Published: July 2010

AbstractIn the mixing of prepared casein glues with water in quantity, the difficulties met with, namely lump‐formation and air‐entrainment, arise from difficulties experienced by the particles in penetrating the water surface, especially if the water already has part of the casein dissolved in it. It is shown that the mixing problem can be solved by carrying out the operation on a continuous basis, and using centrifugal forces to submerge the particles; a machine has been built in which correctly proportioned streams of casein powder and water are passed into a specially designed centrifuge cup, continuously discharged at the top through a scoop‐tube; a scraper provides reflux near the base, and air is removed centripetally as the materials ascend the divergent walls. The machine absorbed only 1/15 h.p. and yielded a virtually faultless mix at rates up to 20 1b. per minute.
The ignition of inflammable gases by sparks from aluminium paint and rusty steel
Authors: Kingman F. E. T. , Coleman E. H. , Rogowski Z. W. 
Published: July 2010

AbstractIn certain circumstances steel coated with aluminium paint can emit sparks when struck with a metal striker, and such sparks may ignite mixtures of inflammable gases or vapours in air. The sparks are due to the thermite reaction between iron oxide and aluminium, and therefore are produced only in the presence of iron oxide. The extent of this hazard depends on the nature of the paint; it is increased if the painted steel is subjected to heat.This work was therefore carried out to determine the effect of the nature of the paint, and the temperature to which the paint might be subjected in use on the tendency to produce incendive sparks (i.e. those liable to ignite inflammable gases or vapours).The investigation was divided into two sections, the first dealing with certain preliminary studies on the conditions necessary for the production of sparks and the reaction involved in spark formation, and the second consisting of a survey of the possible hazard with a representative series of commercial paints.No exact correlation between paint composition and liability to emit sparks was obtained, but none of the commercial oil‐bound paints tested gave sparks unless the specimen had been heated to at least 150°.The paper includes a note by the Senior Chemical Inspector of Factories, outlining the practical application of the results.
The stabilization of soil with resorcinol‐formaldehyde resin for road construction
Authors: Clare K. E. , Packham D. I. 
Published: July 2010

AbstractThe strength and water‐absorption characteristics of three types of soil stabilized with resorcinol/formaldehyde resin have been investigated. The effects of varying (1) the resin concentration, (2) the age of the mixture, and (3) the concentration of added hydrated lime on these characteristics have been examined. The influence of (1) and (3), and of temperature and the presence of certain soil constituents on the setting time of the resin has also been studied.Small proportions (1 to 10%) of the resin were found to increase the seven‐day strength and reduce the water absorption of the compacted soils. Setting of the resin was accelerated by the addition of hydrated lime and by increasing the temperature.
Heat‐transfer coefficients for industrial gases
Authors: Lohrisch F. W. 
Published: July 2010

AbstractIn order to find out the correct size required for heat exchangers, waste‐heat boilers, gas coolers, etc., heat‐transfer coefficients are needed. Although the available literature provides us with the most recent formulae for these coefficients it is nevertheless difficult to assemble all the technical data of the required dimensions. This is especially tedious for those who deal only occasionally with the subject.The physical and chemical properties of the gases are given partly in British and partly in metric units. Thus the inevitable conversion needed to reduce all the figures to the one system of measurement requires much time and study if mistakes are to be avoided. Furthermore, the values given for the thermal conductivity of gases differ in a remarkable degree in the various available lists which, also, ignore many of the more recent valuable experimental figures.The writer has therefore prepared charts for the rapid determination of heat‐transfer coefficients and the presentation of new data based on recent experimental figures for the thermal conductivity of single gases and of gaseous mixtures. These charts are applicable to the gases commonly used in industry.
The mechanism of the catalytic oxidation of sulphur dioxide with a commercial vanadium catalyst: A kinetic study
Authors: Calderbank P. H. 
Published: July 2010

AbstractThe kinetics of the oxidation of sulphur dioxide with oxygen using a commercial vanadium pentoxide catalyst has been investigated. Experimental conditions have been chosen such that the reaction has been carried out isothermally in a flow‐type reactor at temperatures (360° to 450°) and conversions (up to 10%) where the reverse reaction may be ignored.The results, analysed in conjunction with the relevant adsorption isotherms and rates of adsorption on the clean catalyst, indicate that the rate‐determining step is the rate of reaction between gaseous oxygen and chemisorbed sulphur dioxide.The adsorption isotherms, which are Langmuir in character, indicate the presence of at least two different types of active centres. Both oxygen and sulphur dioxide are reversibly chemisorbed, oxygen being weakly bound with a heat of adsorption of 6·4 kcal. and sulphur dioxide strongly bound with a heat of 28·8 kcal. There is evidence that both adsorbed species possess considerable mobility on the surface.Measurements of the rates of adsorption of SO2 and O2 on the clean surface indicate that oxygen is adsorbed by a second‐order mechanism at a slower rate than the observed rate of reaction, whereas sulphur dioxide is adsorbed by a third‐order mechanism at a much faster rate than the rate of reaction. Adsorption equilibrium of SO2 may be assumed, under the conditions of reaction, without sensible error.Adsorption‐rate measurements of both SO2 and O2 indicate that the number of active centres (defects) increases with temperature, according to a relationship of the type d ln L/dT = A/RT2 where L = no. of active centres, as suggested by Volkenstein (1949).With SO2, reaction between it and an active centre requires no activation energy, the increase in rate with increase in temperature being due entirely to the increase in the number of active centres. With O2, a small activation energy may be required, although the main increase in rate of adsorption with temperature is similarly due to the increase in the number of active centres with temperature.Some interesting comparisons are made between the results of these adsorption measurements and recent work on the semi‐conductivity of oxide catalysts, notably by Bevan & Anderson (1950) and Garner, Gray & Stone (1950). Several points of similarity are noted which indicate lines for further work.Finally, a mechanism for the catalytic oxidation of sulphur dioxide is proposed, the main features of which are: magnified image.
Ideal copolymers and the second‐order transitions of synthetic rubbers. i. non‐crystalline copolymers
Authors: Gordon Manfred , Taylor James S. 
Published: July 2010

AbstractTheoretical and practical evidence is put forward to show that copolymers can be treated like solutions of small molecules in the interpretation of packing phenomena, and that ideal volume‐additivity of the repeating units in copolymers is frequently realized. On this basis equations are derived for predicting θ, the second‐order transition temperature, of binary copolymers from the two second‐order transition temperatures of the pure polymers and their coefficients of expansion in the glassy and rubbery states. Previous mechanistic theories of the second‐order transition temperature of such copolymers are thus superseded by a general reduction of the problem to the mechanism of thermal expansion. Practical applications to the choice of monomers in producing synthetic rubbers are outlined, and attention is drawn to the importance of second‐order transitions in kinetic measurements on the reactions of polymers.
Physical evaluation of small samples of plastics
Authors: Bessant K. H. C. , Dilke M. G. , Hollis C. E. , Millane J. J. 
Published: July 2010

AbstractExperimental methods are described for the evaluation of the important mechanical properties of (a) hard plastics, (b) elastomers, when only small amounts of the materials are available. For thermoplastics of type (a), the impact strength was determined by a Charpy‐type test on notched square‐section bars of dimensions 4 cm. × 0·3 cm. × 0·3 cm. cut from strain‐free moulded plates. Softening point was determined by measuring the dilatometric second‐order transition temperature. A qualitative indication of moulding properties was obtained using an Atkinson–Nancarrow plastometer.For materials of type (b), tensile and elongation testing of dumb‐bell specimens in which the effective portion measures 20 mm. × 5·3 mm. × 0·5 mm. gave reproducible results for plasticized polyvinyl chloride. Details of methods of preparing the stock, if high reproducibility is to be obtained, are given. Refractometric determination of second‐order transition temperature was used to measure the brittle temperature. Resilience testing was carried out on specimens measuring 1 cm. × 1 cm. × 4 mm., the apparatus being described.A method for investigating the volatility of plasticizers in small specimens of plasticized polyvinyl chloride is given.
Studies in the corrosion of metals occasioned by aqueous solutions of some surface‐active agents. II. Mild steel
Authors: Ross T. K. , Holness H. 
Published: July 2010

AbstractThe action of dilute aqueous solutions of representative anionic, cationic and non‐ionic wetting agents on mild‐steel sheet has been studied. Three types of water have been used: London tap‐water, distilled water, and tap‐water softened by the zeolite base‐exchange process. The effects of varying the pH of the water used from 2 to 12, and of temperature changes, have been investigated.Most of the anion‐active agents used caused adsorption of organic anions, either on the metal itself, or on the initial corrosion products, so modifying the normal action of plain waters. The cation‐active agents did not produce adsorbed films, but the alkalinity of triethanolamine solutions reduced the extent of rusting.Changes in the pH of the water used to prepare solutions produced little effect, although increased pH caused greater activity in solutions of cationic agents containing bromine.In general, rise of temperature caused increased attack, although the reduced solubility of oxygen mitigated this effect.Results have been expressed graphically and a mechanism is suggested.
Studies in the corrosion of metals occasioned by aqueous solutions of some surface‐active agents. III. Tin
Authors: Ross T. K. 
Published: July 2010

AbstractThe action of dilute aqueous solutions of representative wetting agents on sheet tin has been studied. Solutions have been prepared from distilled water, and London tap‐water with and without zeolite softening. The effect of varying the pH of these waters, and of temperature changes, has been investigated.‘Sulphonated’ castor oil, triethanolamine, and the non‐ionic agents were without effect on tin, but all other agents produced attack. A feature of this attack was the formation of white crusts of corrosion product, surmounting a deep black pore surrounded with interference tints. Tap‐water solutions were generally less corrosive than those prepared from softened or distilled water.Increase of temperature caused increased attack, and in some instances reduced pH also encouraged corrosion.All results have been expressed graphically, and a mechanism is suggested.
N‐propyl and ISOpropyl acetals of glyoxal: Reaction of commercial aqueous glyoxal solutions with propan‐1‐ and ‐2‐ols
Authors: Duval B. , Hall R. H. , Howe B. K. 
Published: July 2010

AbstractThe acid‐catalysed reaction of excess propan‐1‐ol with commercial aqueous glyoxal solution (cf. MacDowell & McNamee, 1944) readily yielded 1:1:2:2‐tetra‐n‐propoxyethane as main product. When excess propan‐2‐ol was employed complex acetals were obtained, including 2:3:5:6‐tetraisopropoxy‐1:4‐dioxan and stereoisomeric forms of 2:3:6:7‐tetraisopropoxyperhydro‐1:4:5:8‐tetraoxanaphthalene. Unsuccessful attempts were also made to prepare 1:1:2:2‐tetraisopropoxyethane from ‘polymeric glyoxal hydrate’ and from glyoxal bis‐bisulphite compound.The analytical determination of 1:1:2:2‐tetra‐n‐propoxyethane was investigated and a gravimetric method employing p‐nitrophenylhydrazine was evolved.
The isolation and examination of films from metal surfaces: An improved technique
Authors: Nurse T. J. , Wormwell F. 
Published: July 2010

AbstractThe technique used at the Chemical Research Laboratory for the removal of oxide films from metal surfaces has been improved, with the objects of obtaining larger pieces of film and of facilitating their manipulation. The improved technique, entailing reinforcement of the film by Formvar (polyvinylformal) resin, is described and examples are given of the application of the method.
The volume‐time‐temperature relationship of polystyrene
Authors: Millane J. J. , McLaren Sheila M. 
Published: July 2010

AbstractThe equilibrium volume‐temperature relationship for solid polystyrene has been investigated by a dilatometric method. The results show that, under equilibrium conditions, the volume is a strictly linear function of the temperature in the range 50–120° and that an apparent transition point is observed only when non‐equilibrium conditions obtain, thus confirming claims of previous workers over which there has been some controversy.
A sparingly soluble hexamethonium salt and its applications: Some observations on allied quaternary ammonium salts
Authors: Barber H. J. , Gaimster K. 
Published: July 2010

AbstractThe preparation and properties of hexamethonium ‘embonate’, a sparingly soluble salt of hexamethonium (hexane‐1:6‐bistrimethylammonium) with ‘embonic acid’ (2:2′‐dihydroxy‐1:1′‐dinaphthylmethane‐3:3′‐dicarboxylic acid), are described, as well as its use as an intermediate in the preparation of soluble hexamethonium salts.A number of new bisquaternary ammonium salts have been prepared.The formation of sparingly soluble salts by hexamethonium and other bases is described and discussed.
Retention by wood of copper and zinc from aqueous solutions of their salts
Authors: Ripley‐Duggan B. A. 
Published: July 2010

AbstractThe retention of metal is defined as the quantity bound by a given weight of wood, after washing out unchanged salt. The retention is shown to result from ion‐exchange with hydrogen ions and metal ions attached to hydroxyl and carboxyl groups occurring in natural constituents of wood. The effects of such variable factors as the concentration of treating solution, hydrogen‐ion concentration, species of wood, temperature, and nature of anion, have been studied.The use of copper and zinc acetates results in larger retentions of those metals. For this reason, copper acetate is suggested as a wood preservative.
Heat transfer to boiling liquids at low temperatures and elevated pressures
Authors: Monroe A. G. , Bristow H. A. S. , Newell J. E. 
Published: July 2010

AbstractPrevious work on heat transfer to boiling liquids is reviewed, and the variations in the boiling heat‐transfer coefficient with temperature difference across the film are described with reference to the boiling mechanism and the physical properties of the fluid.Heat transfer to oxygen and nitrogen boiling inside tubes at pressures from atmospheric to 2000 lb./sq. in. gauge has been studied experimentally. Air was used as the heating medium, and on account of the large temperature difference between the heating medium and the boiling liquid all the measurements fell within the metastable film‐boiling range. Within this range the influence of temperature difference, pressure, and mass flow rate were examined. The higher pressures used exceeded the critical pressures of the fluids, and under these conditions the transition from liquid to vapour occurred without separation of two phases. Behaviour under these conditions is compared with that at lower pressures under which phase separation occurs.Under all conditions the boiling coefficient was found to diminish with increasing temperature difference, and to improve with increasing fluid flow rate. At pressures above the critical the rate of heat transfer is influenced by the absolute temperature of the fluid.The results of this work have been used as a basis for the design of atmospherically heated evaporators for liquid oxygen and nitrogen.