bluuebunny/crossref_metadata_2025_split huggingface dataset:
An X‐ray study of some reactions of chrysotile
Authors: Ball M. C. , Taylor H. F. W. 
Published: July 2010

AbstractChrysotile fibres were treated hydrothermally with aqueous suspensions or pastes of MgO, SiO2, Al2O3, Fe2O3, Ca(OH)2, Ca3SiO5 and β‐Ca2SiO4. Partial or complete reaction often occurred, but the fibres persisted as pseudomorphs which were studied by X‐ray fibre rotation photographs. Those of the products which did not contain calcium, such as Mg2SiO4, Mg3Si4O12H2 and Mg(OH)2, were usually formed with a definite crystallographic orientation relative to that of the chrysotile. A mechanism is proposed to explain this, based on the assumption that reaction occurs by migration of cations (Mg2+, Si4+, Al3+, Fe3+, H+) through a relatively unaffected oxygen framework. Products containing calcium, such as CaMgSiO4, were unoriented. This is attributed to the fact that their oxygen frameworks are more open than those of the compounds not containing calcium; because of this, their formation requires destruction and rebuilding of the crystal structure. The significance of these results for the manufacture of autoclaved asbestos cement products is briefly indicated.
Compacts of powdered material as porous bodies for use in sorption studies
Authors: Sereda P. J. , Feldman R. F. 
Published: July 2010

AbstractDetails are given for the production of rigid porous bodies (compacts) made by compacting under high pressure fine powders in the particle range of 10—0·01μ of silica, calcium carbonate, plaster of Paris and molecular sieves. These compacts were used as samples to study sorption and related dimensional changes. The results were used to compute spreading pressure by applying the Gibbs adsorption equation and allowed derivation of the Δl/l vs φ plots using the Bangham relation.With compacts made from molecular sieves, it was possible to study the forces imposed on the particles by water entering or leaving the micropore system.
Studies in trans‐esterification. I. Synthesis of n‐alkyl methacrylates
Authors: Haken J. K. 
Published: July 2010

AbstractThe preparation of n‐alkyl methacrylates by trans‐esterification has been studied. An optimum procedure for the synthesis of n‐butyl methacrylate was developed by examining the suitability of quinol as polymerisation inhibitor and the effects of catalyst concentration and of the mole ratios of the reactants used. The mole ratio of alkanol to acid was particularly important, the optimum being much lower than that previously reported. The conclusions where they can be compared are in agreement with the results of similar work reported by Dvořkák in 1958.By the method proposed, the reaction period and the time to recover the ester were reduced, and the yield was greatly increased. The general applicability of the method was established by the preparation of a series of n‐alkyl methacrylates.
Selective liquid ion‐exchangers
Authors: Clingman A. L. , Parrish J. R. 
Published: July 2010

AbstractWater‐insoluble long‐chain derivatives of various complexing agents have been prepared, and their solutions in organic solvents have been tested as selective liquid ion‐exchangers. Polymers swollen with these solutions were tried as solid ion‐exchangers in packed columns. In some cases rapid separations of metals were obtained.
Note on ‘a chromatography unit, with automatic sampling, for kinetic studies’
Authors: Spolnicki J. , Crooks W. M. 
Published: July 2010

AbstractSince the publication of the previous paper1 the design of the sampling valve has been improved. It was found that the P.T.F.E. seals were ‘flowing’ into the spaces left between the shaft and the valve body, due to high temperature and constant shaft movement. This was causing a leak of the carrier gas into the sampling chamber.
Sucrose acetoacetates
Authors: Dalton L. K. 
Published: July 2010

AbstractDiketen and sucrose react in dimethylformamide in the presence of triethylamine to form a mixture of sucrose acetoacetates. Excess diketen gives an almost fully substituted ester as a syrup. Sucrose esterified with three moles of diketen can be resolved into fractions containing principally the mono‐, di‐ and tri‐classes of acetoacetates. Sucrose esters of acetoacetic acid alone, or mixed esters with another acid, condense with formaldehyde to yield resins.
Quantitative study of the oxidative discoloration of ethyl linoleate. I. Oxidation in the bulk phase
Authors: Franks F. , Roberts B. 
Published: July 2010

AbstractThe atmospheric oxidation of ethyl linoleate has been studied in the bulk phase at 22 and 50°. The concentrations of conjugated dienes, conjugated trienes (diene ketone), and the development of a yellow coloration were obtained as functions of time from extinction coefficients measured at 234, 268/275 and 350 mμ respectively. The energy of activation of the initial hydroperoxidation reaction agrees well with previously published data. The kinetics of hydroperoxide decomposition have been studied. There appears to be a direct relationship between the rate of hydroperoxide decomposition and the rate of yellowing. The conjugated diene ketone which is formed by a second‐order hydro‐peroxide decomposition is itself oxidised, but no simple relationship can be found between the rate of oxidation and the rate of yellowing. It is therefore concluded that the diene ketone is not a colourless precursor of the yellow compounds.
Vapour pressure and vapour density of halothane (2‐bromo‐2‐chloro‐1,1,1‐trifluoroethane)
Authors: Bottomley G. A. , Seiflow G. H. P. 
Published: July 2010

AbstractThe vapour pressure, in the range −50° to the normal boiling point (50‐2°), and the vapour density, in the temperature range 0–60° and at pressures up to the saturation vapour pressure, of halothane have been determined; the values are presented as equations. The vapour pressures and second virial coefficients are tabulated at temperature intervals of 10°, and gas densities at the same temperature intervals and pressure intervals of 100 mm. Hg.
‘Unexpected’ aldehydes in the oxidation products of octadecenoates
Authors: Horikx M. M. 
Published: July 2010

AbstractDuring the autocatalytic oxidation of esters of oleic acid (9‐cis‐octadecenoic acid) and petroselinic acid (6‐cis‐octadecenoic acid) at moderate temperatures, volatile aldehydes are produced. They consist mainly of the four aldehydes predicted by the α‐methylenic free‐radical chain theory. Also significant amounts of lower ‘unexpected’ aldehydes are present; they are likewise produced during hydroperoxide decomposition in the absence of oxygen. ‘Higher’ aldehydes are virtually absent.The conversion of methyl petroselinate hydroperoxide on a Celite/dinitrophenylhydrazine‐hydrochloric acid column yields the DNPHs of aldehydes, aldehyde esters and conjugated keto‐octadecenoates. The aldehydes are the same as the volatile aldehydes produced during autoxidation; and it is concluded therefore also the lower aldehydes are formed directly from the hydroperoxides.The formation of lower aldehydes can be explained by assuming the presence of bishydroperoxides as minor primary oxidation products, formed in an intramolecular chain‐propagation step. An explanation is suggested for the relatively small yield of aldehydes during hydroperoxide decomposition under anaerobic conditions, in comparison with the amount formed during oxidation.
Quantitative study of the oxidative discoloration of ethyl linoleate. III. Some kinetic aspects of the early stages of the hydroperoxidation reaction
Authors: Franks F. , Gent M. , Roberts B. 
Published: July 2010

AbstractThe formation of conjugated diene hydroperoxide during the early stages of the autoxidation of ethyl linoleate in air and pure oxygen has been studied at 22° and 50°. The published rate equations which have been proposed for the autoxidation of olefinic systems have been integrated and the experimental results fitted to the integrated equations. In order to obtain a reasonable fit to the data, the decomposition of hydroperoxide must be taken into account. The rate constants and activation energies associated with the formation and decomposition of ethyl linoleate hydroperoxide have been obtained and are compared with previously published values.
The emission of corrosive vapours by wood. I. Survey of the acid‐release properties of certain freshly felled hardwoods and softwoods
Authors: Arni P. C. , Cochrane G. C. , Gray J. D. 
Published: July 2010

AbstractThe importance has been assessed of various factors responsible for the release of corrosive vapours from certain freshly‐felled hardwood and softwood species on exposure to high humidity and temperatures in excess of 30°. Variables studied include (i) season of felling, (ii) differences between sapwood and heartwood regions, (iii) initial acid content of the timber on felling, (iv) rǒle of non‐volatile extractive components in catalysing release of corrosive vapours and (v) inhibition of enzymic reactions by mild chemical sterilisation. Although the release of volatile acid is closely related to the loss of bound acetyl groups from the wood substance, indicating autohydrolysis of acetate in the cell wall material, the vapour corrosivity of a timber species is not directly related to its bound acetyl content. The presence of very small free acetic acid contents (0.01—0.03%) in some freshly‐felled undried woods is shown to play a significant rǒle in promoting rapid release of corrosive vapours by the woods (e.g., sweet chestnut and oak). Sterilisation of sweet chestnut and oak with propylene oxide vapour at ambient temperatures markedly reduces, but does not completely eliminate, release of corrosive vapours by these woods. An accompanying reduction in the proportion of bound acetate groups hydrolysed in the cell wall substance may indicate that the release of volatile acidic products from wood is in part due to a microbiological hydrolysis as well as chemical hydrolysis.
The reaction of 3 CaO,Al2O3 with water in the presence of CaSO4,2H2O
Authors: Stein H. N. 
Published: July 2010

AbstractThe reaction of 3CaO,Al2O3 with water in the presence of CaSO4,2H2O is investigated in suspensions and in pastes. In both, essentially the same sequence of reactions is found, the hydration products being (in the order of their appearance) ettringite, hydrous alumina, calcium aluminate hydrate monosulphate, and sulphate‐free hexagonal aluminate hydrates. In pastes, indications of water transport as an important factor in determining the reaction rate are found. Acceleration of the reaction after consumption of most of the sulphate ions present is probably due to chemical conversion of a retarding hydrate layer.
The influence of movement and temperature on the corrosion of mild steel. II. High purity water
Authors: Butler G. , Stroud E. G. 
Published: July 2010

AbstractThe corrosion of mild‐steel tubing by high‐purity water flowing at velocities up to 400 ft./min. and at temperatures of 25, 40 and 55° has been studied over periods of 1–10 weeks. The extent of attack was measured quantitatively from changes in weight of the tube specimens and qualitatively by visual examination and photography. The composition of the corrosion products was elucidated by X‐ray powder diffraction.The rate of attack, k1, increased with flow velocity, v, up to a maximum at about 200 ft./min. according to an expression of the form
equation image
The rate of attack fell on further increase of flow velocity and at 300 and 400 ft./min., k1 did not differ significantly from its value at 2.4 ft./min.The low values for the activation energies confirm that the corrosion reaction is controlled entirely by the rate of diffusion of oxygen to the metal surface at low flow velocities. At higher temperatures there are indications that both the rate of diffusion and the rate of cathodic reduction of oxygen are involved.The amount of goethite, α‐FeOOH, in the corrosion product increased with flow velocity, which was indicative of the higher rate of oxidation of the ferrous ion initially formed. The decrease in corrosion rate at the highest flow velocities is attributed to the formation by this oxide of a more protective barrier layer.
Reduction of metal oxide fines by direct mixing with mazut. III. Application to pure stannic oxide and cassiterite
Authors: Sadek Hussein , Habashy M. G. 
Published: July 2010

AbstractThe reduction of pure stannic oxide by direct mixing with mazut (a petroleum product) in the presence of lime and water, is studied for various paste compositions. It is found that a paste of the oxide 68—70%, mazut 20%, lime 4—6% and water 4—6%, can be almost completely (> 94%) reduced. The extent of reduction increases slightly with decrease of particle size. Cassiterite fines were similarly reduced under conditions in which were varied (i) the starting temperature of heating; (ii) the duration of heating; (iii) the atmosphere in the reduction process; and (iv) the maximum temperature of heating. Complete reduction (94.3%) was obtained with a paste composed of cassiterite fines (< 0.2 mm. mesh size) 82%, mazut 14%, lime 2% and water 2% by thermal treatment for 5 min. in a mazut vapour atmosphere and a maximum temperature of 1000°. Complete reduction was readily obtained with any starting temperature of heating between room temperature and 900°.
The effects of some organic acids and salts on the setting of gypsum plaster. II. Tartrates
Authors: Combe E. G. , Smith D. C. 
Published: July 2010

AbstractIn continuation of previous work on the setting of gypsum plasters,1 study has been made of the effects of tartaric acid and potassium and calcium tartrates on this reaction.Tartaric acid (like acetic acid) has little retarding power, except in the higher concentrations. The marked accelerating effect of the potassium salt is attributed to precipitation of tartrate ions as calcium tartrate, with the formation of potassium sulphate; this is supported by several similarities between the effects of potassium tartrate and those of potassium sulphate, as determined by Smith et al.2 Calcium tartrate has negligible effect on the reaction.
An approach to applicable inorganic polymers. V. Borazine‐phosphonate systems especially those containing the vinyl group
Authors: Brown G. C. , Deuters B. E. , Gerrard W. 
Published: July 2010

AbstractIn the continued search for useful inorganic polymers, boron‐containing monomers having the vinyl group attached to boron and/or phosphorus were prepared. B‐trimethyl‐borazines (MeBNAr)3 (Ar = o‐ or p‐EtC6H4) were α‐brominated by N‐bromosuccinimide; but dehydrobromination to introduce the vinyl group was of limited success. Vinylboron dichloride reacted with ethyl phosphate or bis‐(2‐chloroethyl) vinylphosphonate to give the alkyl chloride (EtCl or Cl2C2H4) and polycondensates containing presumably P‐O‐B linkages. Similar results were obtained with the vinylphosphonate and B‐trichloroborazine, or B‐trichloro‐N‐tri‐o‐ethylphenylborazine or o‐ethyl‐phenylboron dichloride. Interaction of B‐trichloro‐N‐triallylborazine and tri‐n‐butyl phosphate similarly gave n‐butyl chloride and the B‐O‐P compound.Reduction of functionality of boron and/or phosphorus by attachment of the vinyl group did not lead to a marked improvement in the properties of the condensates. Prospects of incorporating vinyl polymerisation are not promising; nevertheless further knowledge of the factors relating to P‐O‐B and similar polycondensation systems has been gathered.
Reactivity of lime and related oxides. XIII. Sulphating of hydrated lime
Authors: Glasson D. R. 
Published: July 2010

AbstractSamples of quicklime and hydrated lime have been sulphated by sulphuric acid and by sodium sulphate solutions at 22°. Rates of sulphating, changes in surface area and phase composition and crystallite size have been correlated with the surface properties of the initial limes. The products have been compared with calcium sulphate dihydrate directly precipitated from solution by double decomposition, and subsequently aged.In acid sulphating, the gypsum from the quicklime has approximately the same specific surface (and average crystallite size) as that directly precipitated from 0.5 M‐calcium nitrate and N‐sulphuric acid. The more active intermediate hydrated lime dissolves more readily and does not impede the sulphating so seriously as the less active initial hydrated lime samples. The latter give products with larger specific surface (smaller average crystallite size) from the more concentrated acid solutions, where the rapid separation of gypsum ultimately impedes the sulphating of the remaining lime.Sulphating with 0.5 M‐soldium sulphate produces increasing alkalinity until about 16% of both the quicklime and the hydrated lime have been converted to gypsum. The sulphate initially separating, probably as a gel, impedes the reaction. The surface decreases until the gypsum begins to crystallise, but its crystallinity remains inferior to that of the acid‐sulphated lime of much lower specific surface.
Corrosion control in a water cooled stator
Authors: Wall K. H. , Davies I. 
Published: July 2010

AbstractBenzotriazole (B.T.A.) is shown to be a satisfactory corrosion inhibitor for copper in closed‐circuit, water‐cooled stators. Laboratory and plant tests indicate that conductivity increase and copper pick‐up are significantly reduced at concentration levels greater than 20 p.p.m. of B.T.A.
Some analytical implications of the interaction between the water and oxygen permeabilities of polymers
Authors: Everitt G. E. , Potter E. C. , Thompson R. G. 
Published: July 2010

AbstractTubes of polythene, polypropylene, furfural polymer (‘Tygon’) or polytetrafluoroethylene are normally permeable to atmospheric oxygen when deoxygenated water flows through them. Both polypropylene and Tygon can achieve a state of impermeability after prolonged contact with water, and this is due to the steady‐state water transmission through the tube‐wall becoming sufficiently vigorous to exclude the oxygen that attempts to penetrate in the opposite direction. It is shown that the achievement of oxygen impermeability by this mechanism can depend on the cross‐sectional dimensions of the tube. Hence only the smaller of two polypropylene tubes achieved impermeability to atmospheric oxygen. On account of the special conditions required for oxygen impermeability, it is considered that none of the four types of polymer tubing tested in this work is suitable for routine use in the sampling of water before microdetermination of dissolved oxygen.
The reactions occurring during the refining of benzene with concentrated sulphuric acid. II. Removal of thiophen
Authors: Roberts D. , Gore P. H. 
Published: July 2010

AbstractThe reaction involved is of first‐order, but prolonged action of the acid leads to return of thiophen to the organic phase. The velocity constant is directly proportional to, but the time required for maximum extraction is independent of, the amount of acid used. The presence of olefins leads to reduced amount of thiophen removed, but maximum removal is effected in a shorter time. The system does not obey the Arrhenius equation and low temperature is desirable for the process.
Adhesion tests for bituminous materials
Authors: Mathews D. H. , Colwill D. M. , Yüge R. 
Published: July 2010

AbstractA series of aggregates of known road performance with 300‐pen. bitumen in bitumen‐macadam wearing‐courses has been examined by five different, known adhesion (stripping) tests.The results of the Static Immersion and Mallison Tests showed no satisfactory correlation with each other, with the results of other tests or with practical performance. The other three tests gave more satisfactory results which bore some relation to each other and to practical performance. The Immersion Wheel‐tracking Test gave the best general relation to practical performance provided that the effects of stability of partially stripped materials were taken into account as well as the amount of stripping. The Riedel & Weber and Immersion Compression Tests gave good correlation with road performance for mixtures not showing stripping in practice and also detected those mixtures which stripped readily on the road. With aggregates of intermediate road performance, the test results were less satisfactory. There is reason to suspect the validity of both of these tests when adhesion agents are present in the binder.
Viscosity/temperature equations for coal tar pitches and refined tars
Authors: Wood L. J. , Downer M. 
Published: July 2010

AbstractThe viscosities of eighteen tar products ranging from refined tar of 34° equiviscous temperature to electrode binder pitch of 102° softening point (Ring Ball) have been measured between wide temperature limits and within the viscosity range of 10 to 1010 centipoises. The applicability of three equation forms to these results has been assessed. A simple logarithmic relationship in terms of Fahrenheit temperature is satisfactory for most products at viscosities greater than 104 centipoises, but does not apply at lower viscosities or to the harder pitches. A double logarithmic viscosity/temperature relationship fits the results well, except those relating to the hard pitches, but it is insensitive and unreliable at viscosities of about 109 centipoises and greater. A third equation relating the logarithm of viscosity to the fifth power of absolute temperature has been shown to apply over the full range of materials, temperatures and viscosities examined.The significance of the constants used in these equations is discussed with respect to their value in comparing the temperature susceptibility of tar products.It is shown that the correct order of viscosity of a tar product, within the range of materials and viscosities investigated, can be predicted from its softening point or equiviscous temperature and its toluene‐insoluble content.
Reactivity of lime and related oxides. XV. Crystalline forms of sulphated lime
Authors: Glasson D. R. 
Published: July 2010

AbstractChanges in surface area and crystallite size in the interconversions of the forms of sulphated lime have been related to time and temperature conditions.The specific surface increases when hemihydrate, ‘soluble’‐γ‐ and ‘anhydrite’‐β‐calcium sulphate are formed during the thermal decomposition of gypsum. The activation is initially delayed in each dehydration stage, before the products recrystallise to their normal lattice structures. Subsequently, the specific surface decreases (and the average crystallite size increases) as each product sinters.‘Wet’ rehydration of γ‐calcium sulphate rapidly replaces the water in the zeolitic hemihydrate structure, without appreciably ageing it. The less mobile ‘dry’ rehydration in water vapour produces hemihydrate extensively aged. Both ‘wet’ and ‘dry’ conversions of hemihydrate to gypsum are completed with considerable loss of surface. The gypsum crystallinity is more rapidly developed during the ‘wet’ rehydration. Effects of additives on the rehydration and ageing of hemihydrate gypsum plasters have been similarly studied.Anhydrite ‘dry’ rehydrates only very slowly, but ages considerably. ‘Wet’ rehydration slowly produces gypsum of low crystallinity; the surface initially increases, before decreasing greatly as the rehydration accelerates. The rehydration rate finally falls as the material continues to age and improve in gypsum crystallinity.
Hydrous oxides and their cation‐exchange properties
Authors: Heitner‐Wirguin C. , Albu‐Yaron A. 
Published: July 2010

AbstractThe hydrous oxides of thorium and titanium were prepared and their cation‐exchange properties studied. The hydrous oxide of titanium has good physical and chemical stability and shows good exchange capacities within wide ranges of pH and temperature. The kinetics of the cation‐exchange reaction were studied and the diffusion coefficients and energy of activation calculated.
Preparation of 2‐methylanthracene by continuous catalytic condensation of 2,5‐dimethylbenzophenone
Authors: King L. F. 
Published: July 2010

Abstract2‐Methylanthracene can be synthesised by batchwise cyclodehydration of 2,5‐dimethylbenzophenone by the Elbs reaction in about 15% of the theoretical yield, but this can be raised to 63% by use of an activated carbon catalyst in a continuous process with benzene as solvent.