bluuebunny/crossref_metadata_2025 huggingface dataset:
The rearrangement of acetylene, benzene, ethane, ethylene, methane and naphthalene in a microwave discharge
Authors: Vastola F. J. , Wightman J. P.
Published: July 2010

The rearrangement of ethane, ethylene and methane (Group A) and of acetylene, benzene and naphthalene (Group B) was studied in a microwave discharge. Hydrogen was the major gaseous rearrangement product of Group A hydrocarbons with small amounts of low‐molecular weight hydrocarbons. No gases were detectable on rearrangement of Group B hydrocarbons. A film with a characteristic H/C ratio was the rearrangement product of any of the gases. All films took up additional hydrogen from a hydrogen discharge and approached a limiting H/C ratio of 1·6. Films with lower H/C ratios took up proportionally greater amounts of hydrogen. X‐Ray and electron diffraction studies of the films showed that the films were amorphous. Other properties of the films produced from the two groups were markedly different. Infra‐red analyses indicated that the films from Group B were more unsaturated than those from Group A but neither set contained aromatic bonding. The films from Group B exhibited high concentrations of free spins. The results are consistent with a rearrangement mechanism which is independent of the type of bonding in the original hydrocarbon. The mechanism may involve CH.
Equilibrium solubility of calcium sulphate hemihydrate in sodium chloride—magnesium sulphate solutions at elevated temperatures
Authors: Clampett J. B. , Fowler R. T.
Published: July 2010

Results are presented for the equilibrium solubility of calcium sulphate hemihydrate in water containing large quantities of dissolved sodium chloride and magnesium sulphate over the temperature range 200–300°F. The concentrations of sodium chloride and magnesium sulphate in the solution correspond to the quantities of these salts found in sea water.

It has been found that the saturation solubility of calcium sulphate is dependent on the content of magnesium ions as well as the sulphate ions and dissolved sodium chloride in the solution. This information is of particular importance in the evaporation of sea water where the degree of prior precipitation of magnesium hydroxide will directly influence the later deposition of calcium sulphate on heat‐transfer surfaces. The use of the results in this connexion is discussed.
The effects of thermal and R.F.‐activated oxidation on the air reactivity of graphite
Authors: Blake A. R. , Hempstead C. A. , Jennings P. P.
Published: July 2010

The increase in the chemical reactivity of nuclear graphite towards air following thermal and r.f.‐activated oxidation has been compared and evidence obtained for an enhanced reactivity following the activated oxidation, without change in surface area. The dependence of reactivity on surface area has also been studied for virgin and thermally oxidised samples and a linear relation found between the two quantities.
Reactivity of lime and related oxides. XI. Production of dolomitic lime
Authors: Glasson D. R.
Published: July 2010

The calcination of dolomite has been studied by determining the changes in specific surface and phase composition and crystallite size during decomposition in vacuo or in air at a series of temperatures up to 900°.

The overall surface activities of the dolimes are correspondingly greater than those of the ordinary limes obtained in previous investigations. The calcium oxide crystallites are similar in size to those in ordinary limes, but the magnesium oxide crystallites are much smaller. This is due mainly to the greater volume decrease associated with the magnesium oxide formation. However, this oxide is correspondingly less active than that from magnesite. Hence, some of its sintering is evidently enhanced by the presence of the calcium oxide.

At lower temperatures, i.e., below 700° in air, some of the carbon dioxide evolved inhibits the decomposition by recombining with the newly‐formed calcium oxide; this reduces the surface activity of the product. At higher temperatures, the surface activity is also reduced by impurities with lower melting points generally enhancing sintering of the dolime.
Rate‐controlling step and rate equation for the reduction of haematite with hydrogen in a fluidised bed
Authors: Venkitakrishnan G. R. , Bhat G. N.
Published: July 2010

Considerable difference of opinion exists regarding the mechanism and the rate‐controlling steps in the reduction of iron oxides. The mechanism of reduction of haematite as such with hydrogen has been investigated using data obtained during reaction in a fluidised bed at 600–900°. The analysis presented indicates that in the early stages of reduction the primary resistance is due to gaseous diffusion through a boundary layer on the particle surface, and most of the reduction and also the overall reaction appears to be controlled by diffusion through the solid oxide body. Based on these observations, a generalised rate equation valid within ± 6% has been proposed.
The effect of water flow on leaching rates of antifouling paints : Consideration of mechanism and preliminary results of laboratory tests
Authors: Wilkie E. T. , Edwards A. C.
Published: July 2010

The rate of loss of copper from many antifouling paints has been found to be 2–4 times greater from ships while steaming than from raft panels. For paints having relatively high cuprous oxide and low rosin contents, evidence is presented that the effect is due not to erosion, but to accelerated solution made possible by substantial removal of diffusion layers by the turbulent flow conditions over a ship's hull.

A apparatus designed to enable leaching rates to be measured at low and high water speeds (1 and 20 knots) is described. Preliminary results show that the usual criteria for turbulent flow and its effect on diffusion to or from a surface do not apply in the case of a paint, the surface layers of which develop into a skeleton of insoluble constituents. With additional turbulence stimulation, an acceleration factor of about 3 is obtained at first, but later the value falls to about 2. It is concluded that further study of turbulence‐development is required.
Manganese in the chlorine dioxide bleaching of kraft pulp
Authors: Press R. E.
Published: July 2010

Manganese in the pulp during the bleaching process has a marked effect in reducing the reflectance of the pulp. This effect is most notable in the chlorine dioxide bleaching stage. The effect is variable depending on the stage and solubility of the manganese contamination, the final pH of thc pulp, the filter water used in washing the pulp and other unknown and variable factors. The manganese contamination of unbleached pulp is largely removed in the chlorination stage, but subsequent contamination is more difficult to remove although a final acid wash does improve the reflectance.
Oxygen deficiency in perovskite‐type compounds of calcium
Authors: Coates R. V. , McMillan J. W.
Published: July 2010

Replacement of tetravalent manganese in calcium metamanganate (CaMnO3) by trivalent iron, and of tetravalent titanium in calcium titanate (CaTiO2) by trivalent iron and aluminium has been made. In each case it was found possible to obtain continuous replacement up to a limit of 50%. The pseudo‐cubic perovskite cells of CaMnO2 and CaTiO3 became genuinely cubic for greater than 25% replacement, and the cubic lattice parameters were measured at 50% replacement. Oxygen deficiencies of about one in twelve must exist in the 50% replacement compounds to maintain the ionic charge balance.
Sorption of long chain normal paraffins in molecular sieves
Authors: Burgess C. G. V. , Duffett R. H. E. , Minkoff G. J. , Taylor R. G.
Published: July 2010

Recent studies in these laboratories of the sorption of n‐paraffins (in the C4—C20 range) in specially treated 5A molecular sieves have revealed that both temperature and molecular weight have somewhat unexpected effects on the isotherms determined by a McBain spring balance method (at 300–400°). The results do not agree with predictions in the literature that, with increasing carbon number, the isosteric heats of sorption should rise at a constant rate. Above C10, − ΔH decreases, temperature dependence becoming almost zero in the region C15—C20. The results are compared with the limited amount of published data, and discussed in terms of the configuration of the sorbed molecules, and of unusual entropy effects. The deductions are supported by some measurements, also reported, for the sorption of nC8—nC17 in 13X sieves.
The promotion of dropwise condensation by monolayers of radioactive fatty acids I. Stearic acid on copper surfaces
Authors: Tanner D. W. , Pope D. , Potter C. J. , West D.
Published: July 2010

A study has been made of the promotion of dropwise condensation by monolayers of stearic acid‐I−14 C on copper. The desorption of promoter during condensation was followed by 14C counting and by autoradiography, and the accompanying increase in wettability was characterised by changes in heat transfer. Rough surfaces were not promoted by a Langmuir monolayer. On a smoot surface the life of dropwise condensation was 10–100 min. Sulphiding the surface before depositing the monolayer increased the life ten‐fold. It was shown that complete coverage of the surface by promoter is not necessary for the promotion of dropwise condensation. The desorption of promoter was uneven and some promoter invariably persisted after the surface had become completely wettable. Condensation was always accompanied by the dissolution of copper, and the change from dropwise to filmwise condensation is attributed to the combined effects of corrosion and promoter desorption.
Chemical aspects of the production of television‐tube screens. I. Reaction of potassium silicate in solution. Effect of impurities
Authors: Lines F.
Published: July 2010

In the manufacture of television‐tube screens, the phosphor powder is attached to the inside of the glass front of the tube by means of soluble silicate adhesive. The usual process uses potassium silicate and an ‘additive’ salt such as barium nitrate to set the binder between particles. The basic barium ion‐colloidal silicate reaction has been investigated using a simple flocculation test to assess reaction rate. For any specified potassium silicate solution, this rate was proportional to [barium]2/[silicate]. Larger colloidal silicate units, i.e., more concentrated solutions, reacted more quickly. Iron and aluminium impurities in the silicate provided nuclei speeding up the reaction, which were sensitive to pH change by dilution, becoming more effective at lower concentrations and with time after dilution. Their effect was proportional to their concentration in the silicate. A flocculation test for silicate purity is suggested.
Reactions of formaldehyde with aromatic amines
Authors: Farrar W. V.
Published: July 2010

As a result of the re‐examination of earlier work on these reactions, the following findings are recorded:

Reaction of certain primary arylamines with formaldehyde in neutral solution has given substances of two new types, viz. 3,5,1‐dioxazines and 1,5‐dioxa‐3,7‐diazacyclo‐octanes.

A study of the complex reactions which occur between formaldehyde and para‐substituted primary arylamines in acid solution has led to the revision of some structures in the literature, and the preparation of novel compounds.

Reaction of formaldehyde with o‐tolidine and with o‐dianisidine in concentrated sulphuric acid has given derivatives of dibenz(c,e)oxepin.

Formaldehyde reacts with arylamines having a free para‐position, in the presence of acidified thiosulphate, to give derivatives of dibenzyl sulphide and dibenzyl polysulphides.
New catalysts for the exchange of deuterium between hydrogen gas and liquid ammonia
Authors: Kenyon A. R. , Pepper D.
Published: July 2010

By experimental study of the rate of exchange of deuterium between hydrogen gas and liquid ammonia, in the presence of potassamide, it has been found that certain organic amines have a catalytic effect. Use of pyrrolidine or dimethylamine with potassamide solutions could reduce the cost of heavy water produced by the ammonia‐hydrogen exchange process.
Evaluation of the durability of roofing bitumens
Authors: Martin K. G.
Published: July 2010

A wide range of types and grades of roofing bitumen have been subjected to bulk heating, pressure oxidation, solar exposure and water immersion separately, and the resulting changes in rheological properties determined.

Particular attention was given to the use of a sliding plate microviscometer and the means of overcoming complexities of non‐Newtonian behaviour and shear rupture to develop evaluations, oxidation resistance and solar exposure resistance, involving initial viscosity, rate of increase of viscosity and a critical viscosity at rupture. Results of these tests are discussed in relation to the performance of the bitumens when exposed outdoors for 2 years as model roofs with various surfacings and evaluated by visual rating, microviscometry, and solvent analysis. Agreement is good and the advantage in durability by using as low a softening point bitumen as possible is indicated except for aluminium‐painted coatings.
The extraction of molybdenum from radioactive wastes
Authors: Jenkins I. L. , Wain A. G.
Published: July 2010

The extraction of molybdenum from aqueous nitric acid containing various fission products has been examined. A separation of molybdenum and of zirconium and niobium from the long‐lived fission products 90Sr, 99Tc, 106Ru, 137Cs, 144Ce and 147Pm is possible with alkyl phosphoric acids. Separation of molybdenum from zirconium and niobium can be achieved by back‐extraction into an aqueous mixture of ammonium fluoride and nitric acid.
The viscosity of coal tar distillates
Authors: Briggs D. K. H.
Published: July 2010

Viscosity determinations demonstrate that log (viscosity of tar distillates) varies linearly with reciprocal absolute temperature. Values at 20° for a variety of tar oils vary linearly with average boiling point of the sample and values extrapolated to the average boiling point are approximately constant. Using this information, a nomogram has been constructed which will enable prediction of the absolute viscosity of a tar oil at any temperature if its average boiling point is known, and comparisons are made with data for pure compounds.
Alkyloxymethyl ethers of cellulose
Authors: Ames G. R. , Sanders J. C.
Published: July 2010

Cellulose, in the form of cotton fibre or cloth, and hydrocellulose react with alkyl chloromethyl ethers in dimethylformamide or dimethyl sulphoxide at room temperature. No base or catalyst is required.
The sublimation of granular solids
Authors: Rushton A.
Published: July 2010

The sublimation rates of cylindrical pellets of camphor, naphthalene and benzoic acid have been measured at various temperatures and absolute pressures. At a certain temperature‐difference between the pellet and the hot surface beneath, the vapour generation was sufficient to cause the pellet to float and move across the surface. A theoretical examination of this condition has been made, and an equation derived by which the time required for complete sublimation of the pellet may be calculated. Measured and calculated sublimation rates are found to be in close agreement.
Vapour‐liquid equilibria: Systems: (1) Acetone‐ethyl acetate; (2) acetone‐n‐propyl acetate
Authors: Subrahmanyam V. , Murty P. Dakshina
Published: July 2010

Isobaric vapour‐liquid equilibrium data have been determined for the binary systems acetone‐ethyl acetate and acetone‐n‐propyl acetate at 760 mm. total pressure using a modified Colburn still. The vapour‐liquid equilibrium data for both the systems are satisfactorily correlated by Wohl's two‐suffix equations. The behaviour of both these systems, as well as that of acetone‐n‐butyl acetate reported earlier is in conformity with Ewell's classification of liquids, in exhibiting positive deviations.
The reaction of sugars with alkyl halogenomethyl ethers
Authors: Ames G. R. , Blackmore Hazel M. , King T. A.
Published: July 2010

Alkyl chloromethyl ethers react readily with sugars in DMF solution only in the absence of a base, even though the reaction produces an acid‐labile acetal and hydrogen chloride. The effect on the reaction of variations in the alkyl group, halogen, sugar, solvent, temperature and reaction time are described.
Thermal decomposition of hydrated UO3
Authors: Landsperský H. , Sedláková L. , Jakeš D.
Published: July 2010

Calcination of ammonium polyuranate at temperatures between 350 and 600°, with a rate of temperature increase of 1°/min., yielded amorphous UO3 having surface area of about 30 m.2/g. More rapid increase of temperature gave mixtures of amorphous UO3+β‐UO3 with no reproducible surface area. To obtain pure amorphous UO3, the mixtures were hydrated in water or in steam and then dehydrated. During hydration, the surface area decreased and the decrease continued during subsequent calcination, to give a final surface area between 3 and 5 m.2/g.
Preparation of some novel diphosphorus compounds. I. 1,4‐phenylene‐diphosphorus compounds
Authors: Chantrell P. G. , Pearce C. A. , Toyer C. R. , Twaits R.
Published: July 2010

The preparation of p‐phenylenebis(tetraethylphosphonous diamide), and its conversion to the corresponding diphosphonous and diphosphonic acids, is described.
The corrosion of stranded, tinned‐copper cable in aqueous zinc chloride fluxes containing ammonium chloride
Authors: Clarke G. B. , Golden J.
Published: July 2010

The rate of corrosion of stranded tinned‐copper cable by aqueous fluxes based on zinc and ammonium chlorides is critically related to the percentage of the latter present. Below 50% ammonium chloride, the rates for solutions of mixtures of the salts are almost as low as that for zinc chloride solution alone, where the time to destroy the tin coating and attack the underlying copper is generally of the order of 300 days or more. For compositions higher than the range 60—70% ammonium chloride, the time to attack the underlying copper falls to the order of 10 days or less, this time becoming proportionately shorter until, for ammonium chloride solution alone, it is less than 24 h.

This phenomenon has been linked with migration of flux solution along the cable via the spaces between strands. Migration for solutions containing less than 50% ammonium chloride is negligible, but for higher concentrations it is appreciable. Supporting work with glass capillaries has shown that at 70% ammonium chloride, the migration is accompanied by the maximum relative enrichment in this salt. It is suggested that this migration‐enrichment is the cause of the steep increase of rate of attack at this range of composition and that attack is initiated by transported material rich in ammonium chloride.
The effect of heat upon inorganic cements
Authors: Rickles R. N.
Published: July 2010

The effect of heat on three inorganic phosphate systems (namely aluminium, boron and zirconium) is studied by X‐ray diffraction, differential thermal analysis and vapour effusion techniques. The reaction temperatures, products of reaction and the heat associated with the reaction were evaluated. The vapour pressure–temperature relationship of a subliming species was developed using the Knudsen approach.
Effect of surface treatment on the efficiency of stainless steel packings
Authors: King P. J. , Walmsley P. N.
Published: July 2010

The separation efficiency of triangular‐pyramid‐type Stedman packing made from stainless steel gauze has been investigated with both organic and aqueous test mixtures at atmospheric and under reduced pressure. For the organic system the packing was found to be most efficient at 310 mm. Hg. With the aqueous test mixture, scatter and irreproducible results were obtained and it has been shown that this was due to the wetting characteristics of the stainless steel gauze. Untreated stainless steel packing is unsuitable for heavy‐water concentration. Improvement in the wetting properties of the gauze by treatment with potassium permanganate led to similar efficiency with both aqueous and organic test mixtures.
Quantitative study of the oxidative discoloration of ethyl linoleate. II. Oxidation on a cotton substrate
Authors: Franks F. , Roberts B.
Published: July 2010

The atmospheric oxidation of ethyl linoleate on a cotton substrate has been studied at 22 and 50°. The concentrations of conjugated diene hydroperoxide, conjugated triene diene ketone, and the development of a yellow coloration were obtained as functions of time by reflectance spectrophotometry at 234, 268/275 and 350 mμ respectively. Both the primary and secondary stages of the oxidation were affected by pretreating the cotton with sodium carboxymethyl cellulose and sodium ethylenediaminetetra‐acetate. A qualitative similarity exists between the extinction coefficients obtained from this investigation and those calculated from a bulk‐phase oxidation, but reflectance measurements at 234 mμ indicate that the conjugated hydroperoxide formed in the initial stages of the oxidation is considerably less stable on the cotton substrate than in the bulk‐ester phase.
Correlation of binary vapour‐liquid equilibrium data
Authors: Jonah D. A. , Ellis S. R. M.
Published: July 2010

A three‐constant conic equation is proposed for correlating and testing the consistency of nonideal and near‐ideal binary vapour/liquid equilibrium data.

The conic equation is based on the geometry of excess thermodynamic functions and the constants are simply related to the partial molal excess functions at infinite dilution and to the maximum value of the excess function.
Current density required for cathodic protection
Authors: Sawyer L. J. E. , Routley A. F. , Chapman D. A. , Crennell J. T.
Published: July 2010

Laboratory investigations have been made of the dependence of current demand on cathodic potential, water‐speed and temperature for steel and copper cathodes. At constant water‐speed and temperature, change of potential in the range −0.7 to −1.0 V (compared with Ag/AgCl reference electrode) required small increases in current density. Apart from the large relative increase in current density required to maintain constant potential involved in initial disturbance from the motionless condition, the current‐density requirement was less than doubled for a doubling of the water‐speed. The effect of rise in temperature was to enhance the ratio increase in current density/increase in water flow.

The current density requirements of steel and copper were closely similar. Surface preparation of the specimens was found to be critical.
Surface properties of hydrolysed titania. IV. Rates of sorption on porous titania
Authors: Harris M. R. , Whitaker G.
Published: July 2010

A technique is described by means of which the pressure changes accompanying the sorption of a gas by a solid adsorbent at −195.8° in a conventional low‐temperature volumetric adsorption apparatus can be followed on a pen recorder. Measurements of both the rates of adsorption and desorption have been taken at all parts of the isotherms for a wide range of samples of hydrolysed titania. Both adsorption and desorption processes have been shown to follow first‐order kinetics. Since the sorption is not isobaric, the rate‐constants calculated from these results will not be the absolute values, but are sufficiently accurate to show quite clearly the relationship existing between pore'size and rate of sorption. For a particular sample, sorption is slowest when it is taking place into or out of a pore. Thus a slow rate of sorption has been used to indicate the presence of pores in a sample even though no hysteresis is shown; this confirms other evidence which indicates the presence of pores in this type of sample. A comparison of rates of sorption between samples of known pore radii shows that, in general, the greater the pore radius, the slower is the rate with which adsorption or desorption takes place. This has been taken to indicate that diffusion in the sorbed layers predominates over gas‐phase diffusion when sorption is occurring in a pore. Certain desorption points show two different values for the first‐order rate constant, the changeover being after about 70% of sorbate has been desorbed. This is considered to correspond to evaporation from the liquid‐like surface in the pore, followed by diffusion through the adsorbed film once liquid has ceased to exist in the pore.
The absorption of carbon monoxide in an aqueous solution of cuprous ammonium lactate in a packed tower
Authors: Thomas W. J. , Watkins S. B.
Published: July 2010

The mechanism of the absorption of carbon monoxide by an aqueous solution of cuprous ammonium lactate is considered, and equilibrium isotherms and an equation relating temperature and the equilibrium constant are established.

Pilot plant studies give values for HOL and KLa, and the effects of gas and liquid flow rates on mass transfer coefficients are determined.

The solution is viscous and has a surface tension which differs considerably from that of water. The viability of published equations for predicting coefficients and interfacial area are appraised.
The mechanism of electrophoretic deposition
Authors: Brown D. R. , Salt F. W.
Published: July 2010

The conditions under which electrophoretic deposits can be formed from suspensions of a number of metallic and non‐metallic materials have been established, and the zeta‐potentials of the materials have been measured. Calculated values of the minimum field‐strength required to overcome the repulsion between the particles show agreement with the observed values for some materials. For other materials, particularly metallic powders, it is not possible to apply sufficient force by the field to overcome this repulsion. Addition of a suitable amount of certain electrolytes, for example 10−3 M‐aluminium chloride, results in very adherent deposits. Under these conditions the electrolytic reaction produces a binder, such as a polymeric hydroxide, at the cathode, so that the adhesion of the deposit no longer depends only on the London‐van der Waals attractive forces between the original particles.
The reaction of oxygen with metallic chlorides
Authors: Allen J. A. , Clark A. J.
Published: July 2010

The reaction of oxygen with the solid chlorides of copper (I), copper (II), magnesium and yttrium has been examined at temperatures in the range 200—450° and at pressures below 20 cm Hg, in order to try to clarify the behaviour of these chlorides in Deacon and oxychlorination catalysts. Copper (II) chloride neither adsorbs nor reacts with oxygen, while the lower chloride readily reacts to form CuO,CuCl2 (or a mixture of CuO and CuCl2). Both magnesium and yttrium chlorides react to form their respective oxides. For magnesium chloride the reaction proceeds without limit except at the highest temperature studied, while for yttrium chloride the extent of reaction approaches a limiting value. These results are related to energetic criteria previously proposed for these catalysts and the possible need (i) to achieve physical dispersion of the copper (I) chloride in these systems, and (ii) to include only components which exhibit limited, rapid oxygen saturation are indicated.
Electrodeposition of some metals from tetramethylurea
Authors: Billinghurst R. G. , Rajki J. , Rutherford K. G.
Published: July 2010

Zinc, cadmium and bismuth have been electrodeposited on copper from tetramethylurea, a new organic electrolyte. The nature of the deposits so obtained was good. A more quantitative treatment of the electro‐deposition of these metals from this solvent is suggested.
Separation of o‐ and p‐chloronitrobenzene by solvent extraction. I
Authors: Hanson C. , Patel A. N.
Published: July 2010

Phase equilibrium data have been determined for o‐ and p‐chloronitrobenzene in systems containing methanol (both anhydrous and containing 10% v/v water) and n‐heptane and have been used to evaluate the possibility of using distribution between these solvents as a means of separating a mixture of the isomers.
Reduction of hematite with hydrogen in fixed and fluidised beds
Authors: Venkitakrishnan G. R. , Bhat G. N.
Published: July 2010

Reduction of hematite with hydrogen has been carried out in fixed and fluidised beds at identical gas flow rates. Influence of gas velocity and particle size has been ascertained. The performances of the two types of bed for the reduction of hematite with hydrogen have been compared. The observed difference in performance is considered to be primarily due to the solids movement characteristics of systems studied. This is also influenced by the bubbling phenomena occurring in fluidised systems.
The thermal decomposition of ammonium nitrate in fused salt solution and in the presence of added salts
Authors: Barclay K. S. , Crewe J. M.
Published: July 2010

The thermal decomposition of ammonium nitrate in a fused equimolar mixture of sodium and potassium nitrates has been studied. It is shown that the reaction is first order with respect to ammonium ions. the rate of decomposition is increased by cations of a highly polarising nature, whereas anions, such as sulphates, phosphates and fluorides, which act as bases in the system, decrease the rate of decomposition. the observations are in accord with an ionic mechanism for the decomposition of ammonium nitrate, involving the reaction of ammonia with the nitronium ion.
Reaction of silica with tetraethyl orthosilicate
Authors: Duffy J. V.
Published: July 2010

The reaction of tetraethyl orthosilicate with fumed silica at various temperatures was investigated by means of infra‐red spectroscopy and gas chromatography. It was found that essentially no reaction occurred at 25° while at 100°, traces of reaction by‐products were detected after short reaction periods. When the reaction temperature was raised to 165°, the condensation reaction proceeded with both hydrated and predried silica glass. It was shown that silanol sites on the glass do take part in a reaction which results in the formation of new siloxane bonds. These sites can be rehydrated after thermal degradation of the treated surfaces in vacuum.
Solvent effects in the oxidation of sulphur compounds. Anionic oxidation of high molecular weight thiols and disulphides to sulphonate salts
Authors: Wallace T. J. , Schriesheim A.
Published: July 2010

The base‐catalysed oxidation of high molecular‐weight aliphatic thiols and disulphides to sulphonate salts by molecular oxygen has been studied from 23.5° to 80°. The preferred solvent was hexamethylphosphoramide. Generally, yields and selectivities of the sulphonate salts varied from 95 to 99% at 80°. Potassium and sodium hydroxides were equally effective as the base catalysts. Other solvents and bases were explored and factors which control selectivity to the final product determined. The reactions are believed to involve sulphenate ions produced by attack of hydroxide ion on the disulphide linkage. Such species are unstable and may be oxidised directly by oxygen or disproportionate to sulphonate ions and disulphides.
Effect of vanadium pentoxide on gas‐phase combustion. II. The methane‐oxygen system
Authors: Matthews C. J. , Tipper C. F. H.
Published: July 2010

The slow combustion of methane in a static system, using reaction vessels coated with vanadium pentoxide, has been studied. Coating a vessel eliminated autocatalysis and retarded the oxidation, the rate of which was only measurable at above 500°. Both the overall order (5.9) and the overall activation energy (about 78 kcal/mole) were very high and the initial rate was markedly dependent on the pressure and nature of added inert gas. The products were carbon monoxide, carbon dioxide (CO/CO2 ratio about one) and water, with only traces of formaldehyde and formic acid. Packing the coated vessel virtually eliminated the pressure change, the products being almost exclusively CO2, but did not appreciably alter the rate of consumption of methane.

It is concluded that the oxidation involves an unbranched chain mechanism, in which both initiation and termination occur on the walls and the propagation reactions are:

the formaldehyde being rapidly oxidised at the surface so that it cannot act as a branching agent.
Multi‐stage computations for continuous gas chromatography
Authors: Tiley P. F.
Published: July 2010

Results are presented of digital computations for a Lewis—Matheson stage‐to‐stage analysis of continuous gas chromatography. for most of the work a column of 80 stages was assumed, but some computations were successfully made for 190 stages.

Three semi‐hypothetical binary volatile mixtures were considered in turn and it was assumed that each formed a non‐ideal ternary liquid phase with an involatile solvent. on optimising the ratio of carrier‐gas to solvent flow, it is shown that the efficiency of the separation is dependent both on the ratio of solvent to mixture feed flow and also on the column temperature. The temperature effect is considered in some detail in terms of stripping factor profiles, and is shown to be quite distinct from any temperature‐dependency of the relative volatility.

A comparison is made between the results of the stage‐to‐stage analysis and those of standard short‐cut methods.
Thermal treatment of thorium oxide gel at low temperatures
Authors: Mikhail R. Sh. , Fahim R. B.
Published: July 2010

Investigations were carried out on the variation of the specific surface area of thorium oxide gel upon thermal treatment in air at temperatures between 35° and 1000°

The specific surface areas and pore volumes of the parent gel and its various dehydration products were calculated from the adsorption of nitrogen at the temperature of liquid nitrogen. The results obtained were compared with those measured from the adsorption of water, methanol and cyclohexane. The adsorbates were chosen to possess different molar volumes and polarities. Water was used because of its known ability to interact with thoria, and the extent to which this interaction limited its use was tested.

X‐ray and thermogravimetric analyses were also investigated, and certain structural changes after thermal treatment were noticed. The gel was amorphous to X‐rays at temperatures up to 300°, and then it recrystallised to the cubic ThO2. Below 300°, the surface area decreased continuously, probably by a mechanism of diffusion and material transport from wider pores to fill fine pores ( ‘surface annealing’). This was followed at higher temperatures by a crystallisation (activation) stage, and finally, by a sintering or crystal growth stage.
Growth kinetics of ammonium‐ and potassium‐dihydrogen phosphate crystals
Authors: Mullin J. W. , Amatavivadhana A.
Published: July 2010

Growth rates of ammonium‐ and potassium‐dihydrogen phosphate crystal faces have been measured in a simple laboratory apparatus under carefully controlled conditions of temperature, supersaturation and solution velocity. The growth process, which was found to be second‐order with respect to the supersaturation, is considered to be controlled by surface reaction.

Growth rates of the ammonium salt (ADP) are much higher than those of the potassium‐salt (KDP) under equivalent conditions. It is suggested that this is due to the occurrence of hydrogen bonding between ADP molecules, which give larger integrating units (thicker growth layers) than occur with KDP.
The properties of the electrical double layer at a dropping mercury electrode in n‐potassium chloride containing n‐alkyltrimethylammonium ions
Authors: Meakins R. J.
Published: July 2010

In further experiments on the adsorption of n‐alkyltrimethylammonium corrosion inhibitors at a dropping mercury electrode in N‐potassium chloride solution, the potential applied to the dropping mercury electrode was taken as far as ‐1.9 volts S.C.E. The electrocapillary and differential capacitance curves for n‐dodecyl‐and n‐hexadecyltrimethylammonium bromides in N‐potassium chloride were generally similar to those in N‐sulphuric acid, and the calculated surface concentrations of the adsorbed quaternary ammonium ions were almost the same.

The wider range of potential in the present experiments enabled the desorption peaks in the differential capacitance curves for the more dilute solutions to be demonstrated. The stronger solutions gave subsidiary peaks, or steps, which may be associated with the formation of double or multiple layers.

The results of these and previous experiments are explained on the basis that the adsorbed layer of n‐alkyltrimethylammonium ions does not completely exclude solvated ions, but hinders their approach to the metal surface.
Foam separation of colloidal particulates
Authors: Grieves Robert B. , Bhattacharyya Dibakar , Crandall Clifford J.
Published: July 2010

The foam‐separation process may be utilised for the separation of hydrophobic (and hydrophilic) colloidal particulates of a flocculent nature from aqueous suspension by the addition of a surfactant with opposite charge and by gas dispersion through the suspension. Process operation and the significant independent and dependent variables are discussed. A model is presented that divides the process into a basic separation step in which the oleophilic particles are adsorbed at the gas/suspension interfaces of the bubbles and an entrainment step in which bulk solution is physically carried into the foam. The model is used to interpret experimental results for the ferric oxide‐dodecyl sodium sulphate system, from consideration of residual ferric oxide concentrations, foam volumes, and removal ratios. A parameter, relative fractionation, is used to compare quantities of surfactant and particulates in the foam and in the bulk solution. Results are used to contrast the effects of surfactants on the foam separation of various particulates of opposite charge, including Escherichia coli, stannic oxide and kaolin clay, with particular emphasis on effects on foaming ability.
Carbonatation of ca(oh)2investigated by thermal andx‐ray diffraction methods of analysis
Authors: Gillott J. E.
Published: July 2010

The carbonatation of calcium hydroxide has been re‐investigated using thermal andX‐ray diffraction methods of analysis. The crystal size and morphology of Ca(OH)2vary with the method of preparation, which also affects the rate and mechanism of the carbonatation reaction. This is also dependent upon the relative humidity established prior to carbonatation. The form of the thermograms is described and the nature of the changes responsible for the peaks discussed.
Emission of corrosive volatiles from wood. III. Effect of treatment with propylene oxide
Authors: Gray J. D. , Cochrane G. C. , Arni P. C.
Published: July 2010

A study has been made of the release of corrosive volatiles when wood shavings are sterilised by propylene oxide. Sterilisation of sweet chestnut (Castanea sativa), beech (Fagus sylvatica), Norway spruce (Picea abies), Sitka spruce (Picea sitchensis), Douglas fir (Pseudotsuga taxifolia) and Scots pine (Pinas sylvestris) with propylene oxide at varying relative humidities and subsequent incubation at 48° and 100% R.H. gave a variable release of corrosive volatiles but usually tended to increase the amount of acid released.
Activation of quartz by alkaline earth cations in oleate flotation
Authors: Malati M. A. , Estefan S. F.
Published: July 2010

The activating effect of the alkaline earth cations in the oleate flotation of quartz increases with increase in their adsorbability on to quartz i.e. Ca2+ <Sr2+ <Ba2+ ions, although their effect in enhancing the abstraction of oleate by quartz increases in the reverse order. This is tentatively explained by suggesting two types of adsorption of oleate on to the cation‐activated quartz. One type of adsorption is probably due to electrostatic attraction between the adsorbed hydrated cations and the oleate ions and this is assumed to determine the activating effect of the cation. The latter effect seems to depend also upon the attraction of the cation to the quartz surface. Depression of quartz flotation at high pH values and high oleate concentrations has been also discussed.
Phase equilibria in sugar solutions. XII. Ternary systems: Sucrose—maltose/lactose—water
Authors: Kelly F. H. C.
Published: July 2010

Equilibrium phase relationships for the ternary systems of maltose or lactose in aqueous sucrose solutions have been determined at 30°. The results are tabulated and illustrated in appropriate triangular diagrams. Chemical analytical techniques were employed. The solubility of lactose was found to be substantially increased in the presence of sucrose, but otherwise mutual effects on solubilities were not particularly marked.
Hydration of tricalcium silicate
Authors: de Jong J. G. M. , Stein H. N. , Stevels J. M.
Published: July 2010

Results of following the quantities of free Ca(OH)2 and of tricalcium silicate (C3S) during the hydration of C3S, and also the influence of the presence of free CaO on this reaction are in accordance with the hypothesis of Stein & Stevels with regard to the hydration of C3S. at the first contact between C3S and water, a surface hydrate, invisible by electron microscope methods, is considered to be formed and to retard the reaction strongly. This hydrate is thought to change into one which retards the hydration reaction less and changes later into a third hydrate, tobermorite gel.
Selective hydrogenation of benzalacetone
Authors: Abdoh Y. , Darvish M. R.
Published: July 2010

Benzalacetone was hydrogenated using a Raney nickel catalyst, and various amounts of HCl, NaCl and H3PO4 in ethyl alcohol were added to test their inhibiting effect on catalytic activity. In the presence of HCl and H3PO4, Raney nickel lost its catalytic activity, and the rate of hydrogenation was decreased, but NaCl had no effect. While the hydrogenation of the ethylenic bond of benzalacetone was retarded, the decrease in hydrogen uptake by the carbonyl group was affected much more, and the amount of alcohol produced was markedly reduced.
Thermal stability of p‐phenylene sulphide polymers
Authors: Black R. M. , List C. F. , Wells R. J.
Published: July 2010

The thermal stability of a series of linear and branched p‐phenylene sulphide polymers at 350° has been evaluated by differential thermal analysis, thermogravimetric analysis and weight‐loss studies. It has been concluded that there is some indication that the thermal stability increases with the degree of branching present in the polymer and that the stability can be further improved by a preliminary heat treatment in the absence of air. The mechanism of ageing appears to involve a combination of crosslinking, chain scission and oxidation reactions.
Mechanism for the anti‐redeposition action of sodium carboxy‐methyl cellulose with cotton. II. colloid‐stability theory applied to the fibre‐soil system
Authors: Johnson G. A. , Lewis K. E.
Published: July 2010

The deposition of particulate soil on to a fabric in a wash system has been treated as a particular case of the general colloid stability theory of Derjaguin, Landau, Verwey & Overbeek. The zeta potentials on the fabric and the soil in detergent solutions have been calculated from electrophoretic mobility measurements. The colloid stability of the systems was determined by a sedimentation method. In particular, it is shown that the anti‐redeposition action of sodium carboxy‐methyl cellulose may be adequately explained by repulsive electrostatic and attractive van der Waals forces.
Synthesis and spectroscopic study of resins from aroyl propionic acids and formaldehyde
Authors: Price R. C. , Spedding H.
Published: July 2010

Thermoplastic resins have been prepared by the reaction of formaldehyde and aroyl propionic acids derived from the succinoylation of aromatic hydrocarbons. A study has been made of the condensation reaction, and nuclear magnetic resonance (n.m.r.) spectroscopy has been found to be extremely useful in the elucidation of the reaction mechanism. Two types of initial reaction with formaldehyde have been shown to occur: firstly, attack at the aromatic nucleus to give a substituted benzyl alcohol (which may condense further); and, secondly, reaction at the CH2 groups α to C = O groups leading to the formation of a γ‐lactone. The relative extents of the two reactions are determined by the activity of the aromatic nucleus to formaldehyde attack. In the case of resins from 2,4,6‐trimethylbenzoylpropionic acid, γ‐lactone formation is virtually absent and attempts have been made to consider the further condensation reactions of the substituted benzyl alcohol formed initially.
Electron‐activated cracking of gaseous hydrocarbons. I. Effect of process variables on cracking of methane in anomalous glow‐discharges at reduced pressure
Authors: Hesp W. R. , Halasz I. , Gerlach H. O.
Published: July 2010

Cracking of methane in anomalous glow‐discharges in a small bench‐scale apparatus (25mm diameter, 42 mm inter‐electrode distance) at pressures of 20–80 torr, feed flow rates of 5–40 l/h and power inputs of 100–300 W has resulted in high degrees of total conversion (up to 98% on carbon basis) and acetylene formation (up to 60%). Dependence on these process variables of the formation of diffuse and concentrated discharges is described and the desirability of the latter for acetylene formation pointed out. The effect of the process variables on yields is complex, but for a given temperature or contact time, specific energy input is the underlying factor which determines yields. Electron‐activation plays an important role in the cracking reactions. The possibility of practical applications is discussed.
Qualitative and quantitative determination of emulsion‐polymerised binders in latex paints
Authors: Post Mildred A.
Published: July 2010

Methods for the separation and identification by infra‐red absorption spectroscopy of styrene‐butadiene, acrylic, vinyl‐acrylic and polyvinyl acetate homopolymer and vinyl acetate‐dibutyl maleate copolymer in emulsion paints based on these materials are presented. Detailed procedures for their quantitative determination are discussed.
Carbon deposition from irradiated methane
Authors: Blake A. R. , Hilton D. A. , Robins I. H.
Published: July 2010

Carbon‐14 tracer techniques have been used to measure directly the carbon deposition resulting from the radiolysis of methane by itself and in the presence of carbon dioxide, oxygen and graphite. It is shown that carbon deposition is increased in the presence of carbon dioxide and decreased in the presence of oxygen. at high carbon dioxide pressures (40 cm Hg) and high doses (>100 Mrad), the majority of the methane is decomposed to deposit. Irradiation of methane by itself produces less deposit than in the presence of graphite and there is an enhancement of the surface deposit compared with that within the bulk of the graphite.

The results of the analyses for light hydrocarbons produced during methane radiolysis over a range of conditions are also briefly discussed.
Absorption in laminar jets
Authors: Thomas W. J.
Published: July 2010

The precision of laminar jet techniques for the determination of diffusion coefficients in gas‐liquid systems is considered. It is shown that diffusion coefficients for the CO2‐water system can be obtained with a 1–2% accuracy, but that in many cases reported in the literature this precision is not achieved. This is due to abnormalities in the jet at the receiver or to vibration.

The system CO2‐aqueous mono‐ethanolamine is used to assess the accuracy of laminar jets for chemical absorption.
Removal of Zn2+ from the ternary system Zn2+ ‐Na+ ‐H+ by cation‐exchange resin column
Authors: Blake W. E. , Randle J.
Published: July 2010

Very dilute solutions containing zinc sulphate, sodium and sulphuric acid were passed down a column of Zeo‐Karb 225 cation‐exchange resin, and the volume at which zinc first appeared in the effluent (breakthrough volume), together with the volume at which the concentration of zinc in the effluent became equal to its concentration in the influent (equivalent volume), were determined.
Liquid‐liquid equilibrium data for the ternary system water‐isopropyl alcohol‐ethylbenzene at 25°
Authors: Knypl E. T. , Wojdylo S. Z.
Published: July 2010

Liquid‐liquid equilibrium data at 25° for the system water‐isopropyl alcohol‐ethyl benzene together with refractive index and density data for mixtures on the binodal curve, are presented. A number of correlation methods were found to represent satisfactorily the equilibrium data and comparison is made with known water‐isopropyl alcohol‐benzene and water‐isopropyl alcohol‐toluene systems.