bluuebunny/crossref_metadata_2025_split huggingface dataset:
Internal standard method of spectrographic analysis as applied to the determination of lead in high purity zinc
Authors: Griffith Laurence , Kirkbride John N. 
Published: July 2007

AbstractThis report an account of an investigation into the fundamental features of the internal standard method of spectrographic analysis, with special reference to the determination of lead in high purity zinc using the direct current art, which requires the closest control. It corner from the lead anodes used in. tire electrolysis and since their condition, with respect to the transfer of lend from anode to cathode, changes continually throughout the cycle from one cleaning period to the next, the grade of line from any particular row of tanks in the tankhouse must be determined daily, if the cathode sheets are to be sent to the correct molting furnace. For zinc of die casting quality, the British Standards Specification No. 1003 allows only 0·003% each of lead, cadmium and iron. The latter two impurities are easily kept less than 0·001% in the electrolytic line process, but lead requires control. Obviously to keep the tonnage of this grade of mental as high as possible, the lead is run as close to the limit as is safe. The margin of safety depends upon the accuracy of the available methods of analysis.
Note on a method of estimating the prandtl number of liquids
Authors: Denbigh K. G. 
Published: July 2007

AbstractOno of the dimensioluss numbers which outers into the theory of heat transfer in fluids is the Prandtl number. This is defined by the relation: where p is the specific heat at constant pressure, η is the viscosity and κ is the thermal conductivity of the fluid. In the case of gases a theorem of the kinetic theory shows that the modified Prandtl number, cvη/k, should be the same for all monatomie gases, and should have a numerical value of 0·4 independent of temperature. Actual values of this quantity lie between 0·4 and 0·6 for almost all gases, including those which are not monatomie. The true Prandtl number, cvη/k, is also nearly constant, and for almost all gases the values lie between 0·7 and 1·0. Among liquids, however, the values of the Prandtl number vary over a range from 3 to over 10,000. Unfortunately, reliable experimental data on cp, η and κ is available for only a small number of liquids, and this limits the extent to which equations, such as that of Dittus and Boeltor, can be used for the calculation of the film cooficient of heat transfer in liquids. During some work on industrial heat transfer the writer has examined the possibility of relating the Prandtl number with some other physical property whose value is much more generally known.
The heterogeneous acid and acid ‐ salt hydrolysis of secondary cellulose acetate
Authors: Haward Robert N. , White Theodore 
Published: July 2007

AbstractThe heterogeneous hydrolysis of secondary cellulose acetate has been investigated in aqueons solutions of acids and acid salt mixtures. A marked anionic effect occurs with neutral salts increasing the rate of reaction but the lyotropie series is arranged in the opposite order to that reported elsewhere in the case of homogeneous hydrolysis.
Twenty years experience with the dissolved oxygen absorption test in China
Authors: Abbott W. E. 
Published: July 2007

AbstractThe application of the biochemical oxygen demand or dissolved oxygen absorption test in the routine examination of sewage polluted liquid in China probably dates from 1920 when an organisation wan sat up by the Shanghai Municipal Council to deal with the problems arising Iron the installation of a water‐borne sewage system. The limitation of the test were not well known in 1923 when the author joined this organization. It became necessary to carry out very extensive investigation when apparent anomalies were encountered. The results were qualitatively the nine at those recorded by workers elsewhere but differed considerably in dot ill.
The photometric determination of silicon in steels
Authors: Gentry C. H. R. , Sherrington L. G. 
Published: July 2007

AbstractA method for the determination of silicon in steels as the molybdenum blue complex is described. By the use of n number of alternative acid solvent mixtures, the method extends the range of steels which can be analysed by existing procedures. A new reducing agent, a mixture of ferrous sulphate and oxalic acid is used to give the molybdenum blue complex. The method is applicable to tungsten containing steels and to weld metal deposits.
A chemical process for the production of lactic acid from sucrose
Authors: Haworth W. N. , Gregory H. , Wiggins L. F. 
Published: July 2007

AbstractThe reaction between calcium hydroxide and cane sugar under different condition of temperature mid time of heating has been studied, with particular reference to the amount of a pure derivative of lactic acid that can ho isolated front the reaction. The zinc salt has been used for this purpose, and zinc lactate corresponding to 71% of the theoretical yield baa been obtained.
The solubility of calcium sulphate as a factor in the extraction of magnesia from sea water
Authors: Gilbert F. C. , Gilpin W. C. 
Published: July 2007

AbstractThe contamination of sea water magnesia by calcium sulphate has been investigated, and is shown to be due to the decreasing solubility of the Bait in the spent sea water as magnesium is progressively replaced by calcium. The saturation point has been determined by dissolving calcium sulphate dihydrate in samples of treated sea water of varying magnesium content, and has been found to occur at a calcium ion concentration of 96·0 mgm. equivalents per 1.000 gm. when 72·5% of the total magnesium has been precipitated as magnesium hydroxide.
The effect of water contents on the strength of calcium sulphate plaster products
Authors: Andrews H. 
Published: July 2007

AbstractIt is well known that calcium sulphate plaster products deteriorate under persistent damp conditions. This paper deals with the quantitative measurement or the effect of water on strength when present in amounts varying from the small amounts picked up from a damp atmosphere to full saturation. The effects are shown to be of importance both in the use‐ and the testing of these materials.
The life of a cobalt catalyst for the synthesis of hydrocarbons at atmospheric pressure
Authors: Hall C. C. , Smith S. L. 
Published: July 2007

AbstractThe economic operation of a catalytic process on the industrial scale is to a large extent dependent on the period of time for which the entalyst can be maintained in an active condition. From the accounts which have been published concerning the pre‐war operation of Fischer‐Tropsch plants in Germany, it would appear that this period is about 4 or 5 months for the cobalt catalyst used in the synthesis of hydrocarbons at normal pressure, and the manufacture and recovery of catalyst forms an important and expensive feature of the whole process.The work described in this paper shows that a cobalt catalyst supported on kieselguhr and containing thoria and magnesia as activators can be maintained in a high state of activity for periods of the order of 18 months by intermittent treatment with hydrogen under various conditions.
The sorption of methyl bromide by wheat
Authors: Winteringham F. P. W. , Harrison A. 
Published: July 2007

AbstractThe total sorption, and rates of sorption of methyl bromide by whole and milled wheat, by wheat glutenin and by wheat starch, have been studied. An attempt has been made by mathematical treatment of the data to differentiate between the methyl bromide physically adsorbed and that chemically combined in wheat, and in glutenin.The effects of moisture and temperature on the sorption have also been studied. So evidence was found that hydrolysis accounts for the decomposition of methyl bromide in wheat: methylation seems a more likely reaction. If the sorption of methyl bromide by the glutenin studied is typical of that of other protein constituents, it seems evident that the protein constituents are mainly responsible for the sorption by wheat. The sorption of methyl bromide by whole wheat has been investigated theoretically. The order of time required for the decomposition of residual physically held methyl bromide in fumigated whole wheat has been calculated.
Residues in wheat flour fumigated with methyl bromide
Authors: Lewis S. E. , Eccleston K. 
Published: July 2007

AbstractMethods have been developed for the investigation of the nature of the residue in ground grain after treatment with methyl bromide. Evidence has been produced that the residual bromide after 2 hours aeration is of a water soluble nature. The protein fraction of the grain has boon shown to be the most active constituent in the reaction with methyl bromide, and some attempt has been made to determine the groups responsible.
Fabric base plastics. Part I. A reconnaissance
Authors: Pepper K. V. , Barwell F. T. , Hale D. K. 
Published: July 2007

AbstractThe applicability of the “voids theory” to laminates made from a phenolic resin and a loomstate cotton cambric has been studied. The effect of systematic variations in the bonding pressure and in the resin content on the density, tensile strength, Young's Modulus, shear strength. compressive strength and water absorption of the products was determined.
The influence of adsorption on the crystallisation of sucrose from impure solutions
Authors: Coalstad S. E. 
Published: July 2007

AbstractFor many years now the purity of raw‐sugar‐mill molasses has been steady within certain limits and analyses of 60 years ago show marked .similarity with those of to‐day. The reason for this has been obscure, but the writer has now shown that the failure of sucrose to crystallise further from the strongly supersaturated solution (molasses) is duo to the presence of surface activo impurities being adsorbed by tho surfaces of the crystals and thus inhibiting their growth. When these impurities arc removed by the use of excess adsorbent carbon, the sucrose will crystallise practically completely. The reducing sugar‐ash ratio is shown to be unfounded ns a criterion for judging molasses exhaustion.
An electrometric method for the estimation of sucrose and reducing sugars
Authors: Coalstad S. E. 
Published: July 2007

AbstractThe writer has adapted the Dead‐Stop End Point method of titration evolved by C. W. Foulk and A. T. Bawden in 1926 to the volumetric estimation of reducing sugars with Fehling's Solution without previous clarification of the sugar solutions. The end point is detected by the polarization effect at two plain copper electrodes dipping into the solution being titrated, to which an E.M.F. of 10 millivolts is applied. With impure sugar solutions, the impurities act as depolarizing agents, but the writer has overcome this effect by adding 0.3 gram of purified animal charcoal to the solution at the start of the titration. A number of examples is given.
An electronic timing device and reflux ratio controller
Authors: Thacker G. O. , Walker B. Y. 
Published: July 2007

AbstractAn electronic timing device is described, which is designed to operate a magnetically‐controlled reflux dividing head for stills using a total condenser. The timing unit is constructed of readily obtainable radio components and can be assembled by anyone with a good knowledge of electricity. The dividing head is constructed of glass, is suitable for operation at atmospheric or reduced pressure and calibration is virtually independent of the properties of the liquid. The whole is suitable for use by plant operatives.
The spectrographs determination of trace elements in the cathode layer ARC by the variable internal standard method
Authors: Scott R. O. 
Published: July 2007

AbstractThe use of iron as the variable internal standard for the determination of trace elements in the cathode layer are, when the iron varies from two to one hundred per cent of ferric oxide, is discussed. Davidson and Mitchell's method, which requires one trace element working curve of fixed iron content and a correction curve for variation of iron content, is examined. Straight line working curves, of slope approximately unity up to at least five hundred parts per million, are obtained for most of the trace element lines when log intensity ratio, corrected for background, is plotted against log concentration, the curves for different iron contents being parallel but vertically displaced. Straight line correction curves are obtained by plotting this separation of the working curve, due to variation in iron content, against log concentration of iron. Two shortened methods for the derivation of the curves are proposed: in the first, the working and correction curves fan be prepared from a standard material by a single determination of the log intensity ratio of the trace element and internal standard lines, corrected for background; the second employs an observed working curve and an arbitrary correction curve. In the concentration ratio method, in which the working curve itself makes allowance for the variation in internal standard content, the log intensity ratio is plotted against the log concentration ratio and this method has similar limitations to the first shortened method.
Leaching rate tests on anti‐fouling compositions. A testing method for inland stations
Authors: Hanson N. W. , Jervis R. F. 
Published: July 2007

AbstractA method is described for the determination of the rate at which compounds of the toxic metals, copper and mercury, leach into sea water from anti‐fouling compositions. The method is suitable for stations where sea water is not directly accessible. Colorimetric procedures for the determination of copper and mercury in sea water arc described, and such aspects as the state in which the toxic metals arc dissolved, and the stability of the leachates, are dealt with. The practical implications of the functioning of anti‐fouling compositions, and the maintenance of a sufficiently high leaching rate arc discussed, special reference being made to the work of U.S. investigators at the Woods Hole Marine Biological Laboratories.
The thermal decomposition of 1:1:1‐trichloro‐2:2‐di‐(4‐chlorophenyl) ethane (D.D.T.) and some of its phase equilibria
Authors: Scholefield P. G. , Bowden S. T. , Jones W. J. 
Published: July 2007

AbstractThe thermal decomposition of pure D.D.T. at various temperatures has been examined by direct measurement of the hydrogen chloride evolved in the reaction. The evolution of gas is only very slight at the melting point of the compound, but it is rapid in the neighbourhood of 200°. Expressions are given for calculating the amount of gas evolved under these conditions. The phase equilibria of D.D.T. with 1: 1‐dichloro‐2:2‐di‐(4‐chlorophenyl) ethylene, naphthalene and 4 :4′‐diehlorobenzo‐phenone respectively, have been examined. The influence of D.D.T. on the miseibility of phenol and water has also been investigated, and it is shown that the substance can be estimated by measuring the rise in the critical solution temperature.
The determination of the pyrethrin content of dilute preparations of pyrethrum flowers in oil
Authors: Bray G. T. , Lord K. A. 
Published: July 2007

AbstractThe Martin‐Brightwell modification of the Wileoxon‐Holaday mercury reduction method, which was drawn up for the evaluation of pyrethrum preparation in mineral oil containing o% of total pyrethrums, have been critically examined and modified to give accurate results for dilute preparations containing less than 0·2% total pyrethrums.
The viscosity and density of sulphuric acid and oleum
Authors: Bright Norman F. H. , Hutchison H. , Smith D. 
Published: July 2007

AbstractThe viscosity and density of aqueous sulphuric neid solutions of 60 to 100% strength und of oleums over the whole of the available ranges of concentration have been determined at 25°, 45°, 60° and 80° with sufficient accuracy to satisfy technical requirements. The viscosity determinations were made in Ostwald viscometers contained in a thermostat, the density determinations being made immediately afterwards with the material from the same stock. When plotted against concentration of total SO2 the viscosity shows maxima corresponding to 69% and 90% total SO2, i.e. to H2SO4.H2O and H2SO4.SO3 and minima at 77% total SO3 (3H2SO4.H2O); there is also an indication of a discontinuity of gradient at 81·3% SO3, i.e. H2SO4. The density plotted against concentration shows maxima at 79·5% and 92% total SO3 and a minimum at 81·3% total SO3 (99·6% H2SO4) with a discontinuity in gradient.
Solubility as a criterion of purity
Authors: Thorp D. 
Published: July 2007

AbstractA method for the determination of the purity of a compound by means of a series of solubility determinations (described in the case of one impurity by Northrop and Kunitz1) has been shown to give
The number of main impurities present;
the percentage of each impurity;
the solubility of the compound;
the solubilities of the impurities.
The method which may prove very useful, especially in cases where the probable impurities are related com pounds, e.g., other members of a homologous series, has been applied with success to DDT (Dichloro‐diphenyl‐trichloroethane) and to 22′, 44′ 66′ NN′ oetachloro‐diphenyl‐urea.
Danger of explosion in handling ether
Authors: Bailey W. G. , Roy A. 
Published: July 2007

AbstractSerious explosions,1,2 attributed to the use of ether containing peroxides, have occurred in laboratory practice from time to time. It has been claimed that various substances will inhibit the formation of peroxide and thus make the use of ether safe. The claim has been tested in the case of copper, mercury, copper, mercury, copper‐zinc and sodium amalgam, and the usefulness of storing in amber glass has also been tested. Of the inhibitors tried, sodium amalgam was the best, and storage in omber glass delayed the formation of peroxide. None of the devices was completely successful in preventing peroxide formation and the only safe procedure is to test ether for the presence of peroxides before distilling or evaporating, and destroy the peroxide if present before commencing either of these operations.
The viscosity of dilute solutions
Authors: Gourlay J. S. 
Published: July 2007

AbstractDilute solutions of many simple binary mixtures conform to the viscosity relationship:— ηs=η0(1+kθ) Where η5 η0 are the viscosities of solution and solvent respectively, θ is the concentration and k is a constant. The constant k has an approximately linear relationship to the molecular weights of the solutes but varies for different homologous series. Using the I renkel relation for the viscosity of liquids η0=GT0 U/RT it is suggested that a solute may affect (a) G or (b) U or (c) both. When solute and solvent have approximately the same times of relaxation, k is not dependent on temperature but in other cases it is. Under conditions of iso‐viscosity, i.e., for equal values of U/RT dilute solutions of cellulose nitrate in various solvents and solutions of naphthalene in benzol and toluol yield approximately equal values for 1/θ (η6/η0‐1) for a given solute.
South African fish products. Part XXIV.—The occurrence of α‐glyceryl ethers in the un‐saponifiable fractions of natural fats
Authors: Karnovsky M. L. , Rapson W. S. , Black M. 
Published: July 2007

AbstractTho amounts of farmaldehyde generated in the oxidation with periodic acid of the unsaponifiable fractions of a wide variety of fats from marine and other sources have been determined,1 and the results recorded in terms of percentage α‐glyceryl ethers, calculated as selachyl alcohol. It is demonstrated in this way that α‐glyceryl ethers are of wide occurrence in the unsaponifiable fractions from marine fats of many different types. They have been found less frequently, and in smaller amounts in the unsaponifiable fractions of land animal and vegetable fats.
The blending of water with organic solvents by detergents
Authors: Palit Santi R. , McBain James W. 
Published: July 2007

AbstractThe present paper records results of blending water with a variety of organic solvents, using various types of soaps in an attempt to provide a basis for an explanation of the phenomenon of blending. Amine salts of the fatty acids and cation active detergents have been used, since ordinary soaps are not sufficiently soluble at room temperature.
Electro‐tinplate. Part II. The in‐ fluence of coating thickness on the porosity and resistance to corrosion of electro‐tinplate
Authors: Kerw R. , Angles R. M. , Caulfield K. W. 
Published: July 2007

AbstractA study has been nude of the effect of variation in coating thick‐ ness (from 2 to 13 02. per basis box) on the quality of clectro‐tinplate deposited from t i e stannous sulphate and sodium state baths, respectively. Using from two to ten specimens for each determintion, CUNCS have been obtained showing the influence of coating thickness on the thiocyanate, hot‐water porosity, humidity, and salt spray test VBIUCS, and showing the effect of time of exposure out‐of‐ doors on weight increment for a range of coating thicknesses. All of the tests reveal a deterioration in the quality of the deposits as the thickness diminishes. There is a certain minimum thickness, varying somewhat according to the nature of the test applied, below which this deterioration is npid. As estimated by the thiocyanate, hot‐water porosity, humidity, and salt spny tests this minimum thickness is in the vicinity of 12 02. per basis box.
The diffusion of plasticisers from polyvinyl chloride
Authors: Small P. A. 
Published: July 2007

AbstractThis paper discusses the factors controlling the rate of loss of plasticiser from polyvinyl chloride compositions to a surrounding gas phase. These are (a) the rate of diffusion in the solid phase or (b) that in the gas phase; for any set of conditions one or other of these will usually be predominant. The rate of desorption from the solid to the gas phase is not considered likely to be a controlling factor in practical circumstances. When gas phase diffusion is rate‐controlling, the loss rate will depend greatly on the degree of turbulence in the gas phase. Since the diffusion contents of ordinary plasticisers calculated from Gilliland's equation1 do not differ as much as the vapour pressures of the plasticisers, the rate of loss will be roughly proportional to the vapour pressure, at different temperatures or for different plasticisers. When solid phase diffusion is rate‐controlling the loss rate, independent of air velocity, will depend on the dimensions of the sample, particularly on its thickness.
A comprehensive survey of the ascorbic acid content of dehydrated cabbage prepared in the factories operating in the united kingdom in the season 1945
Authors: Price‐Davies W. 
Published: July 2007

AbstractThe ascorbic acid content of dehydrated cabbage prepared in factories operating in the United Kingdom in the 1945 season has been assayed. Statistical analysis of the experimental data shows that the standard Ministry of Food factories and the non‐standard factories produced cabbage of equal antiscorbutic value. The ascorbic acid content of summer cabbage, though less than spring cabbage, shows little variation throughout the season, but there is a tendency for higher values to be obtained at the end of the period considered. Further evidence has been obtained that the retention of ascorbic acid (30%) in dehydrated cabbage when reconstituted and cooked in comparable conditions to fresh cooked cabbage, is the same.