bluuebunny/crossref_metadata_2025_split huggingface dataset:
The ketonization of higher fatty acids with some observations on
Authors: Curtis R. G. , Dobson A. G. , Hatt H. H. 
Published: July 2007

AbstractA number of metallic oxides and carbonates may be used as catalysts for the preparation of dialkyl ketones from higher fatty acids in the liquid phase. All cause violent frothing which can be controlled by adding the fatty acid gradually to the catalyst at the reaction temperature. The various metallic oxide and carbonate catalysts are compared and magnesium oxide is selected as most suited for the commercial preparation of ketones. The most suitable reaction temperature range is 330—360°. The crude ketone is greasy, but its properties arc greatly improved by pressing. During the reaction carbon dioxide is evolved in an amount equal to 94% of that required for complete ketonisation. Small amounts of carbon monoxide and other gases arc also formed. The progress of the reaction has been followed by measurement of the rate of liberation of carbon dioxide and the results arc shown to agree with the supposition that a keto‐acid arises as an intermediate in the formation of ketones. Interruption of the reaction and estimation of the unchanged acid present, together with a knowledge of the amount of carbon dioxide then liberated, allows the amount of keto‐acid present in the reaction mixture to be calculated. This is found to be constant during the early stages of the reaction, but increases greatly when the reaction becomes violent. It is suggested that formation of the salt of the keto‐acid is the rate‐determining reaction and that this reaction is catalysed by the metallic oxide used.
The preparation of mixed benzyl pyridine isomers on a pilot plant scale
Authors: Hands C. H. G. , Whitt F. R. 
Published: July 2007

AbstractA semi‐technical method of preparing a mixture of 2 and 4‐benzyl pyridines at the rate of several cwt. per week utilizing the reaction between benzyl chloride and pyridine is described Satisfactory control of the reaction on the 1 cwt. batch size was obtained by the use of circulating hot oil as the reaction vessel heating medium.
A simple method for the preparation of hydrobromic acid
Authors: Goldschmidt F. , Dishon B. R. 
Published: July 2007

AbstractThe reaction of one g.‐atom sulphur, six g.‐atoms bromine and an excess of water has been studied. The reaction takes place in at least two steps, the first being the formation of sulphur mono‐bromide, the second the reaction of this compound with bromine and water. The reaction results in the formation of hydrobromic acid and sulphuric acid. Hydrobromic acid has a retarding influence on the formation of sulphur monobromide but accelerates the reaction of sulphur monobromide with bromine and water. A method for the preparation of hydrobromic acid was worked out based on these observations.
The methylation of meso‐inositol
Authors: McGowan J. C. 
Published: July 2007

Abstractmeso‐Inositol hexamethyl ether and the acetate of a meso‐inesitol pentamethyl ether have been prepared. These compounds show much less insecticidal activity than “Gammexane” (γ‐1,2,3,4,5,6‐hexachlorocydohexane) to which they arc probably structurally related.
Stoichiometric extraction of mixed acids
Authors: Brancker A. V. 
Published: July 2007

AbstractThe separation of the components of a mixture of acids, the dissociation constants of which exhibit small differences, is a problem of some difficulty. In those cases such as penicillin acids which arc soluble in water and a water immiscible solvent, a mixture of acids is extracted from the aqueous phase, and re‐extracted from the resultant solvent medium by alkali, to give an aqueous solution of alkali salts of a mixture of acids. In the process of determining the pH of the aqueous phase during the re‐extraction with alkali of penicillin acids from the solvent phase, 7 inflexion points were observed in the titration curve corresponding to 7 possible acids and, on the basis of this observation, a method was evolved for the separation of these acids by successive additions of alkali in amounts approximately stoichiometrically equivalent to the quantities of acids present. To make the method of general applicability a case of 4 mixed acids has been theoretically investigated, wherein the titration curve, calculated for the solvent‐aqueous alkali system, shows 4 distinct points of inflexion which would permit of the separation of 4 such acids by stoichiometric extraction.
An apparatus for the detection and estimation of small amounts of chloride
Authors: Scott B. A. 
Published: July 2007

AbstractAn apparatus for the detection and estimation of low concentrations of chloride by means of a cell‐comprising silver chloride and lead sulphate electrodes is described. The method is quick and convenient and the accuracy is of the order of ± 10% down to 1 p.p.m. or less. It is particularly suitable for the determination of small amounts of chloride in boiler water since other anions commonly present do not interfere.
The reaction of sulphur and sulphur compounds with olefinic substances. Part V. Rubber vulcanization
Authors: Bloomfield G. F. 
Published: July 2007

AbstractData presented for a range of vulcanized rubbers prepared under different conditions show that while olefinic unsaturation becomes reduced by vulcanization in the proportion of one double bond for each sulphur atom combined with a C5H‐unit, the original H/C ratio of 8/5 is not altered. The loss of unsaturation is somewhat modified when zinc oxide or certain accelerators are also present. Oxygen has a slight inhibiting effect on vulcanization; hydrogen sulphide and mercaptans markedly catalyse the vulcanization reaction without, apparently, affecting the efficiency of the sulphur cross‐linking reaction.In confirmation of the results of Hull, Olsen, and France1, a small proportion of zinc oxide or a soluble zinc soap promotes a reaction between sulphur and mercapto groups whereby di‐ and poly‐sulphides arc formed with liberation of hydrogen sulphide. The same type of activity is shown by some of the nitrogenous accelerators commonly used in rubber vulcanization. Substantial conversion of mercapto groups into polysulphidc linkages is therefore to be expected when vulcanization is conducted in the presence of these auxiliary substances.
Experiments on the corrosion resistance of porous bronze compacts produced by powder metallurgy
Authors: Hallett M. M. 
Published: July 2007

AbstractTests have been made on the corrosion resistance of porous bronze compacts, produced by powder metallurgy, to a range of acids, alkalis, and salts, under aerated conditions, and in some cases under stagnant conditions, in comparison with the resistance of solid bronze under the same conditions. The corrosion resistance of the two types of material did not differ greatly in many cases, but in caustic soda and in concentrated sulphuric acid, major differences appeared, which were studied in greater detail.
The partition of hydrogen chloride between water and benzene
Authors: Such J. E. , Tomlinson R. H. 
Published: July 2007

AbstractA simple partition method using benzene has been found of practical value in determining the partial vapour pressure of HC1 over aqueous solutions containing also a second solute, the latter being insoluble in benzene, in regions of composition corresponding to the maximum concentration of HC1 in effluent gases permitted by factory regulations. The partition of hydrogen chloride between. water and benzene has been measured at 30° over a wide range of concentrations and over a lesser range at 40°. The data are correlated with other known partition data for this system and with published measurements of hydrogen chloride gas phase concentrations over benzene solutions at 20, 25, 30 and 40°. Over the molality range 7·2 × 10‐6 to 2·73 × 10‐1in benzene, the activity coefficient of hydrogen chloride in benzene has been shown to be unity, and to be unaffected by the presence of the water also in partition equilibrium. It is shown to be a theoretical possibility that combination of HCl with H2O in the benzene might cause the ratio of molality of HCl in benzene (M′t) to activity of HCl in water (aHCl) to increase at dilutions greater than those investigated. The temperature dependence of the partition constant is represented over the temperature range 20‐40° by the equation The difference of partial molar heat content of HCl in the two solvents at infinite dilution calculated from the equation is 13, 600 calorics per g. mol. Correspondingly the heat of solution of gaseous HCl in benzene at infinite dilution is 4660 calories per g. mol.
The prevention of dust explosions caused by high explosive bombs in flour mills
Authors: Burgoyne J. H. , Rasbash D. J. 
Published: July 2007

AbstractThe heavy loss of flour mills under enemy attack from the air was shown to be largely attributable to extensive fires resulting from dust explosions initiated by high‐explosive bombs, and a scheme of protection was worked out by Professor G. I. Finch in the capacity of Scientific Adviser to the Fire Research Division of the Research and Experiments Department, Ministry of Home Security. According to this scheme, propagation of the secondary dust explosion was to be prevented by packets of incombustible dust so placed in the mill buildings as to be broken open, and their contents dispersed by the high‐explosive simultaneously with the liberation of combustible dust (flour, etc.) from damaged plant. Refinements to the original scheme were made as a result of the experimental work described.Flame propagation tests showed that a mixture of 90% powdered limestone with 10% sodium bicarbonate would be a suitable incombustible dust for the purpose; the small addition of bicarbonate greatly enhancing the 'flame‐suppressing power of the mineral dust. Investigations into the agglomerating, caking and segregating characteristics of this and related mixtures, mainly in relation to mixture composition and particle size, were carried out, and indications are given of the way in which these factors may be adjusted to give the best all‐round specification for the mixture. An experimental installation in a flour mill is described.
Synthesis of benzaldehyde, a possible route to toluene
Authors: Hardy D. V. N. 
Published: July 2007

AbstractThe synthesis of benzaldehyde from benzene and carbon monoxide under pressure has been examined with a view its use for the production of toluene. With reference to the aluminium chloride used, the yield of benzaldehyde may reach 85%, but it was found impossible to recover the chloride. Attempts to find an alternative catalyst were unsuccessful. The factors governing the synthesis have been studied and it has been shown that the rate of reaction may be accelerated by adding not only benzaldehyde but also furfural and diethyl ether. The reaction is also accelerated by hydrogen chloride and by small amounts of water, but use of the latter leads to a smaller yield. The mechanism of the reaction is discussed.
Methods for the routine estimation of mannitol, alginic acid, and combined fucose in seaweeds
Authors: Cameron M. C. , Ross A. G. , Percival E. G. V. 
Published: July 2007

AbstractMethods are described for the routine estimation in ground seaweed samples of mannitol by periodate oxidation, of alginic acid by isolation and the displacement of acetic acid from calcium acetate, of laminarin by hydrolysis to glucose and its estimation with the Shaffer‐Somogyi reagent, and of fucose (after hydrolysis) by periodatc oxidation and estimation of the liberated acetaldehyde.
Correction for gamma changes due to variations in exposure and development with reference to spectrographs analysis (two line‐pair method)
Authors: Sanders C. 
Published: July 2007

AbstractThe procedure to be described has been found to be useful in the spectrographs determination of composition by the method in which the log, ratio of deflection is plotted against % content (or log. % content), no intensity calibration being carried out. Essentially the procedure consists of using two line pairs for each determination, one on the positive and the other on the negative side of log. ratio 0·000 Where the log. ratio is reasonably near zero it is, of course, unnecessary to read two line pairs. By placing a straight edge through the log. ratio points on the corresponding composition curves and reading off the composition corresponding to the log. ratio 0·000 on this straight line a weighted average is obtained which corrects for plate response, thus giving a better accuracy than that obtained by the use of individual line pairs and log. ratios uncorrected for intensity by plate characteristic curve technique.
The catalytic ethylation of benzene with ethanol in the gaseous phase
Authors: Cullinane N. M. , Chard S. J. , Meatyard R. 
Published: July 2007

AbstractMixtures in varying proportions of benzene and ethyl alcohol were led over catalysts of the alumina‐silica and alumina type at different temperatures. The best yields of ethylbenzene (about 25%, based on the tenzene consumed) were obtained with the former catalysts, the optimum temperature being) 350°.Ethylbenzene is an important intermediate for the production of styrene, which is widely used for conversion into synthetic rubber and resins. Recently a large number of catalytic methods for the ethylation of benzene have been published, especially in the U.S.A.
Contribution to the direct synthesis of phenylochlrosilanes
Authors: Riccoboni L. , Zotta M. 
Published: July 2007

AbstractThe preparation of alkyl‐ or aryl‐chlorosilanes, extensively studied during the last forty years, is carried out mostly by allowing SiCl4 to act cither on Grignard reagents1 or on alkyl‐zinc or mercury‐compounds.2 The. Fittig‐Wurtz method for the preparation of tetra‐substituted deri‐vates was first utilized by Polis3 and later by Kipping and Lloyd.4 Schumb, Akermann and Saffer found it practical to preparathe sodium organic derivative separately and then to treat‐it with the silicon halide. The action of Grignard reagents on ethyl silicate has been studied particularly by Russian chemists5.
A method for the determination of the apparent density of dry powders
Authors: Ault W. B. 
Published: July 2007

AbstractA description is given of a method of determining the apparent density of dry powders which has proved of great use over a period of 45 years. While it was originally developed for precipitated calcium carbonate it can be applied to powders generally. It has been used to distinguish between various grades of powder and its repeatability is good for this class of test as long as specified precautions arc taken.
The corrosion of metals in atmospheres containing sulphur dioxide. Part I
Authors: Tolley G. 
Published: July 2007

AbstractResults are presented for the corrosion of mild steel, aluminium sprayed and aluminized steel by air containing from 2%‐6% SO2, at temperatures of 300°‐700°. The influence of gas velocity, temperature, and concentration of SO2 has been found. Corrosion time curves up to 40 hours' exposure are given for 0.2% and 4% SO2‐air mixtures at 600°. Small concentrations of water vapour in the gas decrease corrosion of mild steel, but further additions increase corrosion. The results show that the catalytic formation of sulphur trioxide on the surface of the metals is of great importance in determining the rate of corrosion.
Microbiological problems in the manufacture of sugar from beet. II. Losses due to fermentation during the diffusion process
Authors: Allen L. A. , Cooper A. H. , Maxwell M. C. C. 
Published: July 2007

AbstractDuring the process of diffusion the gas which collects at the top of a diffuser contains a decreasing proportion of carbon dioxide and an increasing proportion of hydorgen. Observations on the respiration of sliced beet suggest that this factor may be largerly responsible for carbon dioxide which appears at the beginning of diffusion, but that the rising remperature in the3 battery soon inhibits further plant respiration. Periodic opening of the release cocks, which occurs during operation of the battery, then trends to replace the gases originally present by those released from the juice. These include the products of fermentation, which consist of carbon dioxide and hydrogen.The thermophilic bacterial flora of the diffusing juice consist maninly of lactobacilli and gas ‐forming anaerobes. These appear to be largely responbible for production of gas, formation of invert sugar, and the appearance in the juiice of small quantities of lactic, butyric, and acetic acids. The temperature relations of the strains of these organisms tested in the laboratory suggest that their activities would be inhibited if the temperature of the battery were consistently maintained above 70°
The insoluble matter of coal tar. V. Coal tar resins
Authors: Green S. J. , Mukherji S. M. 
Published: July 2007

AbstractFurther work on resinenes is reported including hydrolysis, bromination, thermal decomposition, dehydrogenation, hydrogenation, and alk line permanganate oxidation. The resinenes give neutral and phenolic products on hydrolysis. Dehydrogenation with selenium gives neutral and phenolic products. Oxidation gives a benzenoid residue including benzene hexacarboxylic acid in addition to more complex water soluble acids. The significance of these results is discussed.
An improved method for the generation of insecticidal smokes
Authors: Heath C. D. 
Published: July 2007

AbstractThe development of an improved pyrotechnic composition for the generation of insecticidal smokes is described. This composition has the advantage over previous compositions that it will burn without flame when placed loosely in an open tin. At the same time, the efficiency of the composition, about 90%, is as high as can be expected for this method of generating smokes.
Chromatography in an explosives laboratory
Authors: Ovenston T. C. J. 
Published: July 2007

AbstractThis paper describes some of the features of the Tswett chromatographic technique suited for application to the examination and study of propellants and high explosives. Particular reference is made to an adsorbent consisting of fine silica gel admixed with a filter and. Adsorption series are given for some high explosives and propellant ingredients and characteristic streak tests are described. Finally, a survey is made of a variety of chromatographic applications to problems ranging from analysis and age assessement of propellants to investigations into the causes of the occasional unforeseen colouring of freshly manufactured fishless cordite.
Drying of granulated materials. Part I. Drying of a single granule
Authors: Van Krevelen D. W. , Hoftijzer P. J. 
Published: July 2007

AbstractGranules of wet marl, suspended from the beam of a torsion balance, were dried in a current of dry air. Two rate periods were observed; during the first the rate of drying remains constant, during the second it decreases. With the aid of the conception of Ceaglske and Hougen on moisture distribution in granular materials equations for the rate of drying during the second stage could be derived which arc proved to be in agreement with the experiments. Besides these theoretical equations dimensionless empirical expressions were derived for the two drying stages which enable the rate of drying of single granules under arbitrary conditions to be calculated.Granules of nitrochalk fertilizer, when dried in the same apparatus, showed quite a different behaviour. At first the rate of drying decreased rapidly and soon reached a constant value. This constant rate was over a thousand times smaller than the rate of drying in the case where mass transfer through the gas film is rate determining. The rapid decrease of the drying me at the start could be ascribed to n filling of the pores by solid ammonium nitrate. As soon as the rate became constant drying took place exclusively by diffusion of water vapour through a thin crystal film which had an average thickness of 10‐3 to 10‐5 cm. In this period the rate of drying was only influenced by temperature and by size and structure of the granule.
The waterproofing of soil by resinous materials
Authors: Clare K. E. 
Published: July 2007

AbstractThe stability of cohesive soils is determined largely by their moisture content, and methods of waterproofing or “stabilizing” soils have an important application in the field of road construction. This paper describes study made at the Road Research Laboratory of a method of waterproofing such soils by the addition of small quantities of two natural resinous match, “Vinsol” resin and rosin. The study consisted of an investigation of the properties of soil containing resin, and of the mechanism whereby the waterproofing action is obtained. It was found that a maximum waterproofing effect is obtained with concentrations of resin of the order of I% by weight of the soil, that the effect may take some time to develop, and that the presence of resin affects the compaction properties of the soil. The waterproofing obtained is only operative when the soil has an acidic reaction, but it is shown that a resinous emulsion can be used to waterproof chalky soil. The Kozeny equation for the rate of capillary absorption of water by soil has been used in assessing the reduction in the rate of absorption caused by the addition of “Vinsol” resin to soil. It is considered improbable that the addition of resin reduces the rate of absorption, either by blocking the major soil pores, or by adsorption on the surfaces of the soil particles. It is shown that a reduction in surface tension, as measured by the force exerted on a stirrup dipping into water, is also not a determining factor. It is considered that the most probable mechanism is one in which molecular films of resin spread out at the air water interfaces in the moist soil. These films resist the entrance of further water owing to the tendency to reduce the total area of the interface, and the compressive strength of the film becomes the determining factor once the film is spread, by reducing the effective surface tension of the soil water. Pressure/ area relationships for films of the resinous materials investigated are presented, showing that the reduction in surface tension obtained due to the compressive strength of the films is of the required order.
Drying of granulated materials. Part II. Drying of granules in rotary driers
Authors: Van Krevelen D. W. , Hofitjzer P. J. 
Published: July 2007

AbstractThe product of residence time (t), number of revolutions of the dryer per unit of time (n), ratio of diameter to length of the dryer.(d/l) and the tangent of the angle of inclination (tan α) appears to be constant for every dryer; given by: tnd tan α/l.The constant c depends on the construction of the dryer and is nearly inversely proportional to the number of steps into which die diameter of the dryer is divided by the lifter construction. The drying rate of granules which contain no soluble salts in a rotary dryer is smaller than in freely suspended state at the same Reynolds number of flow.The ratio qudrying rate in a torary dryer/drying rate of freely suspended granules increases.With the number of revolutions. n. Approximately. q = 1/4 to 1/5 when n = 10 r.p.m. and q ∼ n0.5. The experiments do nit allow quantitative conclusions to be drawn on the rate of drying in the second period. The rate of drying of nitrochalk granules in a rotary dryer proved to be the same as for freely suspended granules at the same temperature.