bluuebunny/crossref_metadata_2025 huggingface dataset:
Physical evaluation of small samples of plastics
Authors: Bessant K. H. C. , Dilke M. G. , Hollis C. E. , Millane J. J.
Published: July 2010

Experimental 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

The 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

The 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

The 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

The 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

The 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

The 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.
Pteridine syntheses. I. Leucopterin and xanthopterin
Authors: Albert Adrien , Wood H. C. S.
Published: July 2010

A convenient procedure is described for preparing pure xanthopterin, in 5‐g. quantities, from leucopterin synthesized from triamino‐4‐hydroxypyrimidine.
Retention by wood of copper and zinc from aqueous solutions of their salts
Authors: Ripley‐Duggan B. A.
Published: July 2010

The 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

Previous 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.
Chromium hexacarbonyl. I. The preparation and stability of chromium hexacarbonyl
Authors: Cumming W. M. , Horn J. A. , Ritchie P. D.
Published: July 2010

I. Recorded methods for preparing chromium hexacarbonyl are reviewed and critically compared. Previous theories on the mechanism of formation from carbon monoxide, chromic chloride, and a Grignard reagent are not wholly satisfactory, and an alternative mechanism is proposed, entailing the formation of an intermediate organo‐chromium‐III dibaiide.

II. Hydrocarbon solutions of chromium hexacarbonyl are decomposed on exposure, in the presence of oxygen, to radiation in the near ultra‐violet, forming an insoluble gelatinous precipitate. In the presence of a molar equivalent of a long‐chain fatty acid, such as stearic acid, precipitation is inhibited, though the carbonyl still decomposes to hydrocarbon‐soluble products. The mechanism of decomposition and inhibition is still obscure.
Purification of potassium nitrate process liquors: Comparison between the filtration, froth flotation and sedimentation of insolubles
Authors: Chodkiewicz S. A.
Published: July 2010

The removal of kaolin, mechanical impurities and calcium, magnesium and iron ions from potassium nitrate process liquor was investigated. The addition of potassium alum and soda‐ash resulted in the removal of the soluble impurities and gave rapid settling of the solids. With the help of potassium oleate and Turkey‐red oil the solids can be removed by means of froth flotation, and this method requires only a small sized installation. The filtration using a sand filter or a filter press proved to be uneconomical owing to the unfavourable filtration characteristics of the impurities.
Physico‐chemical studies on dusts. IV. Accuracy of chemical estimation of free silica in rocks and mineral dusts
Authors: Cumming W. M. , Dempster P. B. , Ritchie P. D.
Published: July 2010

The method of Trostel & Wynne (1940) for the estimation of free silica has been applied to the analysis of coal‐measure rocks, and its suitability critically studied. If two fusions and alkali extractions are carried out, and if corrections are applied for the quartz lost during analysis, and for the presence of resistant minerals, the analytical accuracy is ± 2% in the absence of chalcedonic silica. In its presence the result is low, since the loss of chalcedonic silica during analysis is greater than that of quartz. The method cannot be used to estimate accurately the free silica content of mixtures containing both quartz and cristobalite, since the loss from cristobalite during analysis is again greater than that from quartz.
The preparation of 3:5‐dimethyl‐1‐phenyl‐1:2:4‐triazole
Authors: Komzak A. A. , Polya J. B.
Published: July 2010

Optimum conditions for the laboratory‐scale preparation of 3 : 5‐dimethyl‐1‐phenyl‐1 : 2 : 4‐triazole by the Einhorn‐Brunner method have been studied. The mechanism of the reaction is different from those involved in the triazole syntheses of Pellizzari and Kaiser.
The heat treatment of dolomite. I. The ‘activity’ of lime and of magnesia in relation to their temperature of preparation
Authors: Britton H. T. S. , Gregg S. J. , Winsor G. W.
Published: July 2010

Samples of calcium carbonate and of magnesium carbonate have been calcined for two hours at a succession of fixed temperatures in the range 600° to 1400°. The ‘activity’ of the product–assessed by measurements of the rates of dissolution, of slaking, and of bulk density–shows a maximum at about 900° for calcium oxide and at about 700° for magnesium oxide. A tentative explanation is proposed.
Polycyclic aromatic hydrocarbons as starting materials for the synthesis of dyestuffs
Authors: Holbro Th.
Published: July 2010

This paper is a survey of recent research on the technical use of polycyclic aromatic hydrocarbons, which are now available in large quantities, in the synthesis of dyestuffs. This work has shown that the inclusion of these hydrocarbons may have a beneficial effect on the properties of the dyestuffs. The most interesting results were obtained with the tetracyclic compounds chrysene, pyrene and fluoranthene, for which technical use could be found, particularly in the synthesis of high‐quality dyes, e.g. anthraquinone vat‐dyes.
Sodium benzoate and sodium nitrite as corrosion‐inhibitors in ethylene glycol anti‐freeze solutions. I. Laboratory investigations
Authors: Wormwell F. , Mercer A. D.
Published: July 2010

The addition of 1·5% sodium benzoate and 0·1% sodium nitrite to a 20% ethylene glycol anti‐freeze solution effectively prevents corrosion of cast iron and soldered joints in conditions of intermittent heating. In the absence of benzoate, sodium nitrite protects cast iron but increases the attack on soldered joints in glycol solutions, the intensity of attack increasing considerably over the range 0·1 to 1·5% sodium nitrite.

A short initial period of heating is necessary to ensure complete protection of cast iron in 20% glycol solution containing 1·5% sodium benzoate + 0·1% sodium nitrite. At room temperature without initial heating, 0·3% sodium nitrite is required to protect machined cast iron in 20% glycol solution containing 1·0 or 1·5% sodium benzoate; with 30% glycol and 1·0 or 1·5% sodium benzoate, 0·1% nitrite is sufficient. With ‘as‐cast’ surfaces higher concentrations of sodium nitrite are required to prevent rusting.
The attack of metals by free radicals and atoms
Authors: Thompson F. W. , Ubbelohde A. R.
Published: July 2010

Numerous but scattered reactions are known where the surfaces of metal containers are attacked during the chemical changes in contiguous gases or liquids. In many cases the basic physico‐chemical interpretation of such attack is incomplete. In the present paper a number of examples are discussed in terms of thermodynamics and kinetics.

A consideration of the kinetics may involve atoms or free radicals, and a transient concentration of these may be established which greatly exceeds the equilibrium concentration. This can favour internal reduction of metal carbides, nitrides, sulphides and oxides and can lead to extremely high disruption‐pressures at internal voids in the metal.

Other cases of enhanced attack on metal surfaces due to transient concentrations of atoms and free radicals are also discussed.
Acetylene studies. II. The condensation of acetylene with aldehydes and ketones
Authors: Bergmann Ernst D. , Sulzbacher Max , Herman Daniel F.
Published: July 2010

The preparation of acetylenic carbinols and glycols is described, using as condensing agent the system potassium hydroxide plus acetals (or ethylene glycol dialkyl ethers); this system has an optimum absorption of acetylene at 80°. The mechanism of the reaction is discussed.
Acetylene studies. III. Preparation and reactions of the acetyldialkylcarbinols
Authors: Bergmann Ernst D. , Herman Daniel F.
Published: July 2010

The hydration of the dialkylethynylcarbinols, and the reactivity of the acetyldialkylcarbinols so obtained, i.e. hydrogenation to secondary‐tertiary glycols (and the reactions of the glycols) and reductive animation, have been studied. The amino‐alcohols so prepared, which contain a tertiaryhydroxyl and a primary‐ (or secondary‐) amino group, give Schiff bases or oxazolidines with aldehydes and ketones, and 2‐mercapto‐oxazolines with carbon disulphide or thiocarbonyl chloride. They also condense easily with 1‐halogenoanthraquinones (with their amino group).
The determination of phenolic hydroxyl values (semi‐micro method)
Authors: Brunner H. , Thomas H. R.
Published: July 2010

The various factors affecting the accuracy and procedure of hydroxyl determination are discussed. Phenolic acetates have been found to hydrolyse fairly rapidly during the hydrolysis of anhydrides, a process which is normally carried out at the end of the acetylation reaction, and this is held to account for anomalous hydroxyl values obtained previously for phenolic substances.

A satisfactory semi‐micro procedure has been developed for use with samples of phenols (20 to 80 mg.).

In determining the acid values of phenols and phenolic‐resin intermediates the use of phenolphthalein as indicator is to be avoided. Neutral red is suggested as a suitable indicator.
Determination of sulphate and sulphonate anion‐active detergents in sewage
Authors: Degens P. N. , Evans H. C. , Kommer J. D. , Winsor P. A.
Published: July 2010

Very small amounts of anionic synthetic detergents can be quickly estimated by a modification of the method originally employed by Jones. The effects of various interfering substances can usually be eliminated by a suitable choice of the volume ratio of aqueous and organic phases, and by the number of extractions. However, the effect of thiocyanate at concentrations greater than 5 p.p.m. cannot be wholly eliminated in this way, and two alternative methods of removal by chemical reaction are described. Sulphate and sulphonate detergents can be separately estimated by hydrolysing the sulphates in boiling acid solution and measuring the detergent content before and after treatment. More details of the method are given in the Appendix.
The brittle fracture of tars and bitumens
Authors: Rigden P. J. , Lee A. R.
Published: July 2010

As part of a study of the cracking and disintegration of bituminous road‐surfacing materials, measurements have been made of the tensile strength of tars and bitumens, of tars to which filler has been added, and of tars after exposure to the action of weather. Measurements have also been made of the Fraass brittle temperatures of the materials.

Under conditions of test in which there is no flow, tars, pitches and bitumens have the same brittle tensile strength of about 6 kg./cm.2; this value, which was obtained for materials tested in moulds that imposed lateral restraint, increases to about 30 kg./cm.2 when the specimen has no support at the position of fracture. Weathering of the materials has little effect on the brittle tensile strength, but the measured tensile strength increases considerably when the cross‐sectional area of the test specimen is reduced.

A mathematical analysis of the Fraass brittle test has shown that it is an equi‐viscous temperature test measuring the temperature at which the material has a viscosity of approximately 4 × 109 poises.

Although the addition of filler to tar increases the brittle tensile strength, no significant change is produced in the Fraass brittle temperature because there is a corresponding increase in viscosity.
The role of tannates and phosphates in the preservation of ancient buried iron objects
Authors: Farrer T. W. , Biek L. , Wormwell F.
Published: July 2010

Archaeological specimens of iron are occasionally found to be well preserved under conditions that would normally be regarded as highly aggressive. A striking example arose during excavations at Hungate, York, where iron articles were found in an excellent state of preservation after a period of about 2000 years. Investigation revealed that the lack of corrosion was attributable mainly to inhibition of the activity of sulphate‐reducing bacteria by tannates present in the soil. Phosphates likewise present probably assisted by reason of their known corrosion‐inhibitive properties.
Separation of phenols from coal‐tar hydrocarbons by means of glycerol and aqueous triethylene glycol: Development of a process
Authors: Cumming A. P. C.
Published: July 2010

The present paper is an extension of the work on the extraction of phenol from coal‐tar hydrocarbons, and deals with the separation of mixed phenols from coal‐tar hydrocarbons boiling in the range 170–201°. By subsequent treatment of the extract, a final mixed‐phenols product can be produced containing 0·1% of hydrocarbons or less. The outlines of a process for this separation are included.
The action of metallic nickel on bismuth trichloride
Authors: Cornish E. H.
Published: July 2010

Nickel reacts with dilute aqueous solutions of bismuth trichloride with deposition of elementary bismuth. There is, however, a range of concentration of the salt within which nickel has no action at 25°. At higher temperatures other factors intervene and smooth reaction occurs. The rate of reaction is increased by moderate stirring but decreases with increasing acid concentration.
Flow of concentrated suspensions
Authors: Williams P. S.
Published: July 2010

Part I of the paper deals with the general properties of the flow of concentrated suspensions. The shear stress/rate of shear characteristics of Newtonian, non‐Newtonian, plastic and thixotropic types of flow are briefly set out. The types of suspensions encountered in the paint industry and their flow properties are described, and it is concluded that no generalization is yet possible on the effect of particle size, shape or nature of the chemical interface.

In Part II some recent research on the flow of glass spheres in simple liquids is reported: glass spheres were used because they are geometrically simple and are easily made, and the methods of preparing and fractionating them into different size ranges are described. The importance and difficulty of particle‐size analysis are discussed. Results obtained with suspensions containing different concentrations of spheres with different size‐distributions are given and it is found that the particle‐size distribution very much affects the viscosities of suspensions with more than about 30% of spheres by volume. It was found that the more nearly the particle sizes are equal to each other, the lower is the concentration of spheres required for a given viscosity. It was also found that for particle sizes less than 1/μ in diameter, the smaller the size, the greater the thixotropy.
Acetylene studies. V. Diels‐alder reactions with methylchloroprene
Authors: Bergmann Ernst D.
Published: July 2010

3‐Chloro‐2‐methylbutadiene (methylchloroprene), which can be prepared from ethynyldimethyl‐carbinol by dehydration and addition of hydrochloric acid, gives the normal Diels‐Alder reaction with butyl fumarate, maleic and chloromaleic anhydrides, p‐benzoquinone, acrylonitrile, methyl methacrylate, α‐hydroxyisopropyl vinyl ketone and ββ‐dimethylacrolein, but not with crotonaldehyde, crotonic acid, methyl isopropenyl ketone and ethynyldimethylcarbinol.
The determination of the critical constants of liquid explosives
Authors: Lewis D. T.
Published: July 2010

The critical constants of liquid explosives cannot be measured directly because of the intractable nature of the substances concerned. Equations are developed in this paper whereby the critical temperatures and critical densities of liquid explosives may be determined with a high degree of accuracy from measurements made in an accessible range of the densities and surface tensions of the explosives concerned.

In order to illustrate the application of these equations the critical constants of 2:4:6‐trinitrotoluene (TNT), nitroglycerin and mercury have been calculated and the relationships employed are shown to be of general applicability to a wide range of chemical substances.

The surface tensions of TNT have been experimentally determined, and it is shown that this explosive, when in the liquid state, has normal characteristics.
The separation and determination of mixtures of chlorinated o‐cresols
Authors: Freeman F. , Gardner K. , Pound D. W.
Published: July 2010

Methods of separation of the products of chlorination of o‐cresol are described. The procedure adopted for preparation of the pure chloro‐o‐cresols is outlined, and the development of a rapid method for the estimation of the four cresols appearing in the chlorination product is traced. The method consists in separating, by partition chromatography on kieselguhr, the mixture into two fractions, 6‐chloro‐o‐cresol + 4 : 6‐dichloro‐o‐cresol and o‐cresol + 4‐chloro‐o‐cresol. The components of these fractions are estimated differentially by ultra‐violet spectrophotometry. Results are shown for analysis of mixtures of the pure cresols.
Simplified low‐speed rotor techniques for corrosion testing
Authors: Wormwell F.
Published: July 2010

Several simplified rotor techniques are described. Corrosion is appraised by the measurement of weight‐loss or depth of pitting on specimens in round‐rod or sheet form. With single cylindrical specimens, electrode potentials have been measured under conditions of rotation. The results help to explain the influence of cathodic and anodic polarization on the corrosion of mild steel in sea‐water.
The aggregation of kaolinite
Authors: Gregg S. J. , Hill K. J.
Published: July 2010

A series of fractions of kaolin [smaller than 0.5, 0.5–1, 1–2.5, 2.5–5, 5–10 and 10–20 μ in equivalent Stokes' diameter (E.S.D.)] separated by sedimentation have been investigated by measuring the specific surface area, SA, by gas sorption, the heat of immersion in carbon tetrachloride, the bulk volume, V, and the apparent density in various liquids; the ‘percentage floating in air after five seconds,’ f, has also been determined by dropping down a long glass tube. The value of SA agrees reasonably with the specific area, SD, calculated from the E.S.D. for the 0.5, 0.5–1, and 1–2.5‐μ fractions, but SA/SD then increases with increasing E.S.D. to nearly 4 for the 10–20‐μ fraction; moreover both V (whether measured ‘in air’ or ‘in vacuo’) and f have maximal values for the 1–2.5‐μ fraction. The results point to the existence of two types of aggregate : (a) temporary and loose aggregates in the three smallest particle sizes, and (b) ‘booklets’ in the three largest sizes.
The influence of molecular structure on the oxidation of aliphatic hydrocarbons
Authors: Small N. J. H. , Ubbelohde A. R.
Published: July 2010

From a review of existing studies on the oxidation of hydrocarbons, the relationship between structure and ease of oxidation at low temperatures appears to be quite anomalous, compared with most other hydrocarbon reactions.

Recent experimental results indicate that the anomalous relationship between structure and reactivity is associated particularly with the fate of the energy‐rich peroxide radical, R·*, whose formation and reaction are generally written

Factors which may favour reaction (b) include a low energy of transfer of hydrogen from RH to RO2·, and a high energy content made available for activation by vibration coupling within the hydrocarbon molecule. Collisions of RO2· with hydrogen or mercury hinder reaction (b). In addition to possible vibrational‐energy activation it is suggested that RO2· may exist in more than one electronic state, with different energy contents.
Thermodynamics of formaldehyde manufacture from methanol
Authors: Jones Elwyn , Fowlie G. G.
Published: July 2010

The production of formaldehyde from methanol, either by thermal decomposition, by catalytic oxidation or by a combination of the two, is treated as an exercise in chemical thermodynamics. Simple dehydrogenation of methanol does not appear attractive because it requires temperatures which tend to produce decomposition of the formaldehyde as it is formed. Oxidation of methanol to formaldehyde and steam requires the agency of a catalyst which is active in the region of 300°, the ideal working mixture for an insulated catalyst containing roughly 5 1/2 to 8% of methanol in air. The composite process, in which dehydrogenation and oxidation occur simultaneously, offers certain advantages, and may be expected to give maximum efficiency in the range 500–700°, corresponding to methanol/air mixtures containing 45 to 37% of methanol. Addition of steam to the reacting mixture lowers the catalyst temperature and modifies the product composition accordingly. Rapid cooling of the products to about 300° is essential to avoid regeneration of methanol and decomposition of formaldehyde. An interesting feature is that the straight oxidation‐process operates with mixtures of methanol and air at or just below the lower inflammability limit, whereas the composite process requires mixtures at or above the upper inflammability limit.
The use of the Eschka method for the determination of high sulphur contents
Authors: Mott R. A. , Wilkinson H. C.
Published: July 2010

It is shown that the incineration period for determining sulphur in coal can be reduced, in a well ventilated muffle, to I hour at 775–800°, for a 1‐g. sample with 4 g. of Eschka mixture. The same time can be used for high sulphur contents with 0° i‐g. samples. The essential feature in obtaining complete precipitation of the sulphate ion is to ensure adequate excess of barium chloride of which 10 ml. of 10% BaCl2,2H2O is adequate for sulphur up to 0·08 g., a similar excess being obtained by using 10 ml. with 0·1‐g. samples for sulphur contents of 8–80%. For sulphur contents higher than 80%, 0·1–g. samples, with 70% excess of barium chloride, should be used.

It is shown that the barium sulphate precipitate is most quickly and accurately determined by igniting the wet filter‐paper in a well ventilated muffle, with precautions to avoid shock‐heating.
Use of the membrane filter in the bacteriological examination of water
Authors: Taylor E. Windle , Burman N. P. , Oliver C. W.
Published: July 2010

Molecular or milli‐pore filter membranes have been used for a number of years in Europe. The Goetz type, recently introduced in America, not only retains all micro‐organisms from a large volume of liquid but also can be placed in contact with an absorbent pad soaked with concentrated nutrient solution; this solution passes through the pores of the membrane to the bacteria deposited on its surface, so that they can be cultivated in situ.

The work described below is a preliminary survey to assess the possibility of applying membrane‐filter technique to media and methods commonly used in Britain for the bacteriological examination of water. The chief advantages of the technique are concentration of micro‐organisms, removal of inhibitory substances and saving in glassware and in media preparation.

Further investigations proposed include the examination of a series of samples, the development of a procedure for achieving a rapid result and the isolation of pathogenic organisms from sewage effluents and polluted waters.
New ω‐substituted anisoles. II. Aryloxymethanesulphonates: Reactions
Authors: Barber H. J. , Cottrell H. J. , Green M. B.
Published: July 2010

Aryloxymethanesulphonic acids, ArO·CH2·SO3H, and their salts are fairly resistant to hydrolysis and can be nitrated and chlorinated. The sulphomethoxyl group is ortho–para‐directing in the ratio of about 1:10. 4‐Nitrophenoxymethanesulphonic acid can be reduced to the sparingly water‐soluble 4‐aminophenoxymethanesulphonic acid, the amino group of which retains its aromatic character and can be diazotized and coupled. Alkyl‐substituted aryloxymethanesulphonic acids can be oxidized to the corresponding carboxylic acids. On treatment of aryloxymethanesulphonates with chlorinating agents the SO3H group is replaced by Cl, with the formation of phenoxymethyl chlorides, ArO·CH2Cl. Aryloxymethanesulphonic acid esters can be obtained by treatment of the silver salt of the sulphonic acid with an alkyl iodide.
Froth‐flotation reagents for coal: Distillation fractions of commercial oils and some simple phenolic compounds
Authors: Whelan P. F.
Published: July 2010

Three commercial oils commonly used for the froth flotation of fine coal were fractionally distilled in a high‐efficiency laboratory column. When the individual fractions were tested for flotative power on Gresford and Bedlington fine coals, little variation was found, except that components boiling at temperatures below 180° or above 280° had less power than those in the middle range.

Some 20 simple substituted monohydric phenols of known constitution were subjected to a similar evaluation. They fell into four groups of very different flotative power.

Many physical properties of the fractions and of the phenols were measured. No correlation was found between flotation merit and boiling point, solubility, refractive index or dielectric constant of the reagent, or the surface tension and relative surface viscosity of its saturated solution in water. On the other hand, there was a strong indication that the degree of ionization is important, good frothers for coal having dissociation constants (Ka) less than 10−7 and non‐frothers greater than that value as a rule. The power of the phenols in small amount to reduce or refine the size of bubbles created in water by passing air through a porous disc was also shown to be directly related to their flotation merit.
The thermal decomposition of methyl linoleate hydroperoxide
Authors: Williamson L.
Published: July 2010

Methyl linoleate hydroperoxide produced by ultra‐violet‐light‐catalysed oxidation of methyl linoleate has been thermally decomposed in the presence of excess of methyl linoleate. By carrying out the decomposition in an inert atmosphere it has been possible to trace the true reaction‐products formed by the initial peroxide‐oxygen. New oxygenated non‐peroxidic forms of methyl linoleate, dimeric and trimeric compounds are produced. The dimers have been characterized as carboncarbon‐bonded methyl linoleate molecules, but the trimers are of more complex structure. From the relative proportions of oxygenated monomer and polymeric compounds a tentative mechanism to explain the formation of the reaction products has been advanced.
Rapid determination of glycerol by the potassium periodate method
Authors: Hartman L.
Published: July 2010

A study of the glycerol determination by the potassium periodate method has been carried out with the object of developing a rapid and yet fairly exact analytical procedure. It has been found that the time of oxidation recommended in the existing methods can be substantially reduced without affecting the accuracy of the determination. Several other modifications of these methods are suggested. In particular, the use of potassium dimesoperiodate (dipotassium periodate) instead of the much less soluble metaperiodate (monopotassium periodate) makes it possible to increase the size of the glycerol sample and thus to achieve a greater reproducibility of results.
Phenol‐formaldehyde and allied resins. II. Trinuclear and hexanuclear novolaks
Authors: Davis A. C. , Hayes B. T. , Hunter R. F.
Published: July 2010

2: 6‐Bis‐4′‐hydroxybenzylphenol has been synthesized by isomerization of 2: 6‐bis‐4′‐hydroxybenzylidenecyclohexanone and by condensation of 4‐bromo‐2: 6‐bishydroxymethylphenol with phenol and subsequent reduction of the resulting bromobishydroxybenzylphenol with palladium and hydrogen. 4:4′‐Dihydroxy‐3:5:3′:5′‐tetra‐(2″‐hydroxy‐3″:5″‐dimethyldibenzyl)diphenylmethane, which constitutes the first example of a hexanuclear novolak in which two novolak chains are linked by a central methylene bridge, has been synthesized by condensation of 2:6‐bishydroxymethyl‐4‐bromophenol with 2:4‐xylenol, dehalogenation of the di(hydroxydimethylbenzyl)bromophenol with palladium and hydrogen and condensation of the resulting 2:6‐di‐(2′‐hydroxy‐3′:5′‐dimethylbenzyl)phenol with formaldehyde. The hexanuclear novolak showed a pronounced tendency to form adducts with aliphatic alcohols, recalling the curiously stable additive complex of the tetranuclear p‐cresol novolak and ethylene dichloride. Examination of the X‐ray diffraction of specimens of the solvent‐free hexanuclear novolak and its methanol adduct in the Frevel focusing camera used in the earlier investigation2 showed that, as with the tetranuclear compound and its ethylene dichloride adduct, the lines in the powder photographs were quite dissimilar and apparently unrelated.
The thermal decomposition of anhydrous nitric acid vapour
Authors: Ellis W. R. , Murray R. C.
Published: July 2010

Calculations from published figures of the equilibrium constants for the decomposition 2HNO3 H2O + 2NO2 + 1/2O2 show that the degree of dissociation of nitric acid vapour is quite considerable even at moderate temperatures and reaches 100% at 200° and 1 atmosphere pressure. The rate of dissociation has been studied in glass cells at various temperatures (150–250°), by measuring the concentration of nitric acid through the amount of absorption observed in the 1·4‐μ region of the infra‐red. The significance of the results is discussed qualitatively.
A note on the rapid determination of free formaldehyde in phenol‐formaldehyde syrups
Authors: Haslam J. , Soppet W. W.
Published: July 2010

A rapid method has been devised for the determination of free formaldehyde in phenol‐formaldehyde syrups.

The neutralized alcoholic solution of the sample is treated with hydroxylamine hydrochloride solution and the liberated hydrochloric acid then titrated with standard alkali to pH 3·4 by means of a direct‐reading pH meter.
The variation of the viscosity of gelatin sols with temperature
Authors: Croome R. J.
Published: July 2010

The variation of the viscosity with temperature has been studied on sols of an isoelectric ossein gelatin, and representation of this variation has been found possible by means of an equation of the type ν = AeK/T.

The term A has been shown to be a function of the percentage (weight) concentration of gelatin in the sol.

A working hypothesis has been made that the hydration of the gelatin particles, during soaking, persists on dispersion; the decrease in viscosity with rising temperature is represented as due, in the main, to a progressive loss of the absorbed water back to the free dispersion medium, thereby decreasing the ratio of weight of dispersed phase to weight of dispersion medium.

Expression of the viscosity as a function of this ratio had yielded an equation representing the variation of the viscosity with concentration of gelatin.

The reversibility of the viscosity‐temperature variation has been explained as being due to the rupture and subsequent re‐formation of hydrogen bonds set up between the water molecules and the lyophilic peptide groups in the gelatin particles.
The chlorination of α‐chloroethylbenzene. II
Authors: Webster W.
Published: July 2010

The study of the chlorination of α‐chloroethylbenzene (1′‐chloroethylbenzene) in the presence of iodine as catalyst has been continued in more detail. With concentrations of 2.0% by weight of iodine instead of 0.2% as employed previously, much higher amounts of chlorine react by substitution, and less addition takes place. The formation of styrene dichloride (1′:2′‐dichloroethylbenzene), which results from the use of high iodine concentrations at 20°, is prevented by carrying out the reaction at 0°.

Yields of nuclear‐monochlorinated α‐chloroethylbenzene are about 88% of the theoretical. Styrene dichloride, which gives rise to α‐ and β‐chlorostyrene in the monochlorostyrene obtained on dehydrochlorination, can be estimated in the chlorination product by infra‐red absorption methods.
Adiabatic compression and expansion of polystyrene
Authors: Toor H. L. , Eagleton S. D.
Published: July 2010

Equations relating temperature and pressure for adiabatic compression and expansion of polystyrene are derived from Spencer & Gilmore's equation of state for equilibrium conditions.

The temperature changes determined experimentally are larger than expected and the results are correlated if a constant in the equation of state is altered.

Compressions and expansions are found to be essentially reversible and adiabatic for the time scale of the experiments and for the time scale occurring in injection moulding.
Separation of benzene and n‐hexane by means of ethylenediamine as solvent: Molar solutropy
Authors: Cumming A. P. C. , Morton F.
Published: July 2010

Ternary and quaternary phase‐equilibrium data are presented for the system benzene‐n‐hexane‐ethylenediamine and benzene‐n‐hexane‐ethylenediamine‐water at 20°. This system is solutropic, (i.e. the distribution ratio is reversed in it); to distinguish it from other solutropic systems the term molar solutrope has been proposed, which refers to systems that show a change in sign of the gradient of the tie lines on a molar plot. One other system which has been found to be molar solutropic is acetone‐ethylene glycol‐benzene at 27°.

Ethylenediamine is capable of extracting benzene from n‐hexane and of producing 100% n‐hexane (raffinate) and 85% benzene (extract) as products. The addition of water to the solvent improves the purity of the extract, and at 16% of water a product of 97% pure benzene can be produced.
Corrosion‐inhibitive compositions as temporary protectives of steel against atmospheric corrosion
Authors: Sanyal B. , Preston R. St. J.
Published: July 2010

The value of aqueous inhibitor solutions for the temporary protection of steel has been investigated, and inorganic pastes and organic emulsions have been developed for protecting steel against atmospheric corrosion.

Heavy inhibitor‐salt deposits afford some protection, but bentonite pastes give much longer protection and may have practical applications. The thixotropic properties of bentonite and other materials are particularly valuable when the pastes are applied to inclined surfaces; application may be by brushing, dipping, or spraying.

The further rusting of steel surfaces can be suppressed by the use of bentonite/nitrite pastes, a useful practical application where the cost of de‐rusting a rusted surface might be uneconomic.
Corrosion of aluminium alloys in supply waters
Authors: Porter F. C. , Hadden S. E.
Published: July 2010

The corrosion characteristics of wrought aluminium and a number of wrought and cast alloys when immersed in typical public supply waters under stagnant or slowly moving water conditions have been investigated. Most of the tests have been carried out at room temperature but tests have also been made at temperatures up to 80°. Corrosion‐time curves have been drawn, using pitting depth and loss of weight as measures of corrosion.

Changes in the composition of the waters caused greater differences than changes in alloys, but the order of attack was similar in all waters tested. Corrosive attack was most severe in the harder waters, the typical form of attack being the development of deep pits covered by mounds of corrosion product consisting mainly of aluminium hydroxide (‘nodular pitting’)

Experiments with synthetic waters have shown that this form of pitting develops when calcium bicarbonate, chlorides, copper salts and dissolved oxygen are present together in the water. These constituents are all normally present in various proportions in public supply waters. A mechanism accounting for the development of the pits is proposed.
New ω‐substituted anisoles. IV. Chlorination of anisoles: The preparation and properties of aryloxymethyl chlorides, aryloxymethylene dichlorides and aryloxychloroforms
Authors: Barber H. J. , Fuller R. F. , Green M. B.
Published: July 2010

Chloroanisoles (chlorine substituted in the nucleus) are chlorinated wholly in the side‐chain at 190–200° in the presence of 1/20 molar proportion of phosphorus pentachloride. The three hydrogen atoms of the methoxy group are successively replaced by chlorine, with the formation of the hitherto unknown chlorophenoxymethyl chlorides, chlorophenoxymethylene dichlorides and chloro‐phenoxychloroforms. In the absence of the catalyst a mixture of nuclear‐ and side‐chain‐chlorinated products is formed. With most catalysts other than phosphorus pentachloride chlorination takes place wholly in the nucleus.

Unsubstituted anisoles are chlorinated at 190–200° mainly in the nucleus, even in the presence of phosphorus pentachloride, but methyl‐substituted anisoles give mixtures of nuclear‐chlorinated products, methylphenoxymethyl chlorides and methoxybenzyl chlorides.
New ω‐substituted anisoles. V. Chlorination of aryl dimethyl ethers
Authors: Akerman H. E. , Barber H. J. , Green M. B.
Published: July 2010

Chlorination of quinol dimethyl ether at 190–195° in the presence of 1/20 molar proportion of phosphorus pentachloride gives mainly nuclear‐substituted products. Chlorination of 2:5‐dichloro‐quinol dimethyl ether under similar conditions takes place wholly in the methoxyl groups. The methoxyl groups are attacked alternately until all six hydrogen atoms are replaced by chlorine. Chlorination of 4:5‐dichloroveratrole gives similar results.
New ω‐substituted anisoles. VI. A new route to 2,4‐d compounds
Authors: Barber H. J. , Green M. B. , Zwartouw H. T.
Published: July 2010

2:4‐Dichlorophenoxymethyl chloride, obtained by chlorination of 2:4‐dichloroanisole at 190–195° in the presence of 1/20 molar proportion of phosphorus pentachloride, reacts readily at 60° with sodium cyanide or potassium cyanide in acetone or methyl ethyl ketone containing a little water to give 2:4‐dichlorophenoxyacetonitrile, which can be hydrolysed to 2:4‐dichlorophenoxyacetic acid. A little bis‐(2:4‐dichlorophenoxy)methane and 2:4‐dichlorophenol are formed concurrently. The reaction does not proceed satisfactorily in alcohol or dioxan.
Analysis with double‐beam infra‐red spectrometers
Authors: Bellamy L. J.
Published: July 2010

A number of applications of balanced double‐beam systems are described and their special advantages discussed. Such methods have been used for the qualitative study of oils and paints and for the detection and identification of materials separated in chromatographic columns or on specially prepared paper chromatograms. Applications of such methods to quantitative analysis are also discussed and are illustrated by examples of analyses of cordites and lubricating oils. There are indications that the behaviour of oils undergoing oxidation can be followed in this way.
An infra‐red study of the cis‐ and trans‐isomers of some c18 fatty acids
Authors: Ahlers N. H. E. , Brett R. A. , McTaggart N. G.
Published: July 2010

A detailed quantitative study has been made of the infra‐red spectra between 2.5 and 15.0 μ of some 19 fatty acids, including mono‐unsaturated acids as well as the polyunsaturated acids, conjugated and non‐conjugated.

In some cases the results permit assignment of the cis‐trans‐structure of the double bonds of the fatty acids and are useful in the analysis of isomeric mixtures, such as may arise during the process of dehydrating castor oil and in the preparation of linseed stand oil.
Correlation of the solubilities of gases in low‐vapour‐pressure liquids by an evaporation analogy
Authors: Burrows G. , Preece F. H.
Published: July 2010

In Part I the similarity between the evolution of gas from a liquid, and the evaporation of vapour from a pure liquid, is discussed. Equations are developed which incorporate the energy of cavity formation in the liquid to accommodate the gas molecule, and the interaction energy between the gas and solvent molecules, based on solubility, surface tension and temperature.

Experiments for determining the solubilities of helium in three low‐vapour‐pressure liquids are described in Part II; the results conform to linear plots, according to the equations formulated in Part I.

In Part III, the theory of Part I is applied to the solubilities of air (nitrogen and oxygen) in a variety of petroleum oils ranging from heavy lubricating oils to aircraft fuels; reasonably consistent values were obtained for the radii of the gas molecules, the interaction energies and the heats of evolution. Positive and negative temperature coefficients of solubility are explained by the behaviour of linear plots. The conclusion is reached that the variation of gas solubility with temperature is similar in principle to the variation of vapour pressure with temperature, when allowance is made for the surface tension of the liquid and the polarizability of the gas molecule.