bluuebunny/crossref_metadata_2025_split huggingface dataset:
Conditioning of d2O in heavy water power reactors
Authors: Allison G. M. 
Published: February 2011

AbstractThis report indicates the problems associated with the maintenance of the purity of the D2O in a pressurized heavy water power reactor and how these problems are handled.In a pressurized water power reactor, impurities will be introduced into the coolant and moderator from the corrosion of the steel system. These impurities are mainly particulate and colloidal in nature. They must be kept to a minimum since when circulated through the reactor they become activated by the neutron flux and when deposited throughout the system they make accessibility for maintenance difficult. Impurities may also be introduced into the water from fuel element ruptures. These also create maintenance problems since they are intensely radioactive.Heavy water systems require a constant guard against the introduction of light water which would degrade the D2O and make the operation of the reactor inefficient or perhaps impossible. The isotopic content of the heavy water must be checked constantly. Upgrading may be required periodically or continuously.The general purity of the water in the reactor is maintained by passing a fraction of the main circulating volume through a by‐pass containing a filter and a mixed bed ion exchange resin column. This column serves to remove ionic impurities as well as acting as an efficient filter itself. It is also used to maintain the pH of the water at the desired level whether neutral or alkaline. In the case of heavy water systems the resin must be deuterized before use to prevent degrading the D2O.
Letter to the editor
Authors: Happel John 
Published: February 2011

AbstractRE: Viscous Flow in Multiparticle SystemsThis abstract reviews a series of theoretical studies which has resulted in achieving a better understanding of such phenomena as resistance to flow of fluids through beds, sedimentation of small particles and viscosity of suspensions. There are many systems both in nature and technology involving these types of motion. Examples of commercial applications include the separation of particles by centrifuging and sedimentation, filtration, flow of gases through vessels containing packed solids (kilns, gas producers and blast furnaces), and motion of particles and gases in catalyst contracting vessels.
Flow of compressible fluids
Authors: Powley M. B. 
Published: February 2011

AbstractPreviously derived equations describing compressible flow have been rearranged in terms of known downstream conditions to facilitate determination of unknown upstream conditions. A 650 I.B.M. computor was used to solve the simultaneous equations numerically to permit construction of convenient design graphs in parametric form. Use of these graphs will eliminate a tedious trial and error computation formerly necessary with presently available methods when the upstream pressure and temperature are to be determined in gas flow problems. Application to design is illustrated by a worked sample.
High energy fuels for jet propulsion engines
Authors: Perry C. W. 
Published: February 2011

AbstractSince World War II, the development of jet propulsion engines has fallen into two main categories, i.e. air breathing devices which include the turbojet and ramjet engines, and the rockets which use solid or liquid fuels. A brief review is given of the history and operating principle of each type.The use of fuel energy for power release in jet propulsion engines is based on rate of change of momentum as the fuel is burned either with oxygen or other oxidizer. The basic power and thrust equations are presented. From these equations it is shown that high heat of combustion, ΔH, is the most significant fuel property for air breathing engines, but other properties including molecular weight of the products of combustion and temperature of combustion become equally significant for the rockets. Other desirable properties for chemical fuels are listed.Candidate chemical fuels having higher energy release than hydrocarbons (with oxygen) are tabulated. It is shown that hydrogen, beryllium and boron hydrides have significant potentiality. Hydrogen is difficult to use. Beryllium chemicals are very toxic. Consequently, the boron hydrides and their alkylated compounds show exceptional promise. The properties of these are listed.
Catalytic reforming
Authors: Emms N. J. 
Published: February 2011

AbstractThis paper describes the Catalytic Reforming Process for upgrading naphtha feedstocks to high octanes using a regenerable platinum catalyst. Particular reference is made to the Powerforming Process developed by Esso Research and Engineering Company and in use by Imperial Oil Limited.The various types of fixed bed units are described and a simplified flow plan of a typical Powerforming Unit is illustrated. The general operation of the unit is discussed as well as the primary reactions involved in catalytic reforming. Operating conditions are listed and some product yields and quality are shown in a table for various feedstocks.Regeneration is required to reactivate the catalyst by burning off carbon and sulphur compounds laid down during the oil cycle. A general description of how this is carried out on a unit containing a swing reactor is outlined.
Distribution of residence times in continuous series of mixing zones
Authors: Buckler E. J. , Breitman L. 
Published: February 2011

AbstractTabulated numerical data, nut hitherto available, are presented for the number fraction distribution of residence times of particles in fluid which passes through a series of 1, 2, 3, … up to 75 mixing zones in series. For the special case in which the weight of particles varies linearly with time, the weight fraction distributions of residence time are also tabulated. The theory is recapitulated and extended to include the effect of recycle.
Ultimate velocity of drops in stationary liquid media
Authors: Warshay M. , Bogusz E. , Johnson M. , Kintner R. C. 
Published: February 2011

AbstractThe effects of high field viscosity and of low inter‐facial tension on the terminal velocity of single liquid drops falling through stationary liquid fields were investigated. Drops of tetrachloroethylene, ranging from 0.08 cm. to 1.4 cm. equivalent diameter, were allowed to fall through four different types of field fluids made by the addition of carboxy methyl cellulose, Lytron 890, corn syrup, and glycerine to water. Viscosities varied from 41.3 to 514 centipoises.Low interfacial tension systems were ethylchloroacetate‐water, furfural‐water, and benzyl alcohol‐water with interfacial tensions of 16.43, 5.70, and 4.25 dynes per cm. respectively.For systems of high field viscosity, the usual drag curve appears to be more useful than the correlation proposed by Hu and Kintner. For systems of low interfacial tension (below 20 dynes/cm.) and low field viscosity (of the order of one centipoise) the latter serves to correlate accurately the data of 25 systems.A comparison of the pour technique with the usual nozzle method for the introduction of drops resulted in a terminal velocity difference of less than three percent. Wall proximity corrections were made when necessary.
Principles and operation of an air operated mixer‐settler
Authors: Mathers W. G. , Winter E. E. 
Published: February 2011

AbstractA mixer‐settler for continuous countercurrent solvent extraction is described in which the mixing and pumping of the liquid phases are achieved by air streams.The operating principles of this mixer‐settler are presented in theory and confirmed by experiment. Measurements include interface heights, capacity, air requirements and entrainment of aqueous phase in the solvent under various operating conditions.The main advantages claimed for this unit are.1) Mechanical simplicity and consequent freedom from maintenance.2) Pumps and interface controllers are not required between individual stages.3) Compactness for a given separation.4) Low energy requirements.
Fundamental aspects of solids‐gas flow: Part I: Introductory concepts and idealised sphere motion in viscous regime
Authors: Torobin L. B. , Gauvin W. H. 
Published: February 2011

AbstractThis article introduces a series of analytical and critical literature surveys which deal first with the individual fundamental momentum transfer phenomena associated with particulate motion as affected by particle shape, roughness, acceleration, concentration and rotation, as well as the turbulence characteristics and boundary conditions of the transporting fluid. This information will then be used as a basis of discussion and interpretation of the many investigations of multiparticle solids‐gas conveying systems and contacting techniques reported in the literature.This first paper reviews briefly some pertinent basic concepts of fluid mechanics, and then considers the development of the fluid velocity field and drag for single spherical particles moving rectilinearly at pre‐wake‐forming Reynolds Numbers through an infinite and undisturbed fluid.
An analysis of air and solid flow in a spouted wheat bed
Authors: Thorley B. , Saunby J. B. , Mathur K. B. , Osberg G. L. 
Published: February 2011

AbstractDetailed studies of the air and solid flow patterns in a spouted wheat bed have been made in column sizes up to 2 ft. in diameter. Orifice size, cone angle, bed height and air flow were varied so as to establish their effect on these flow patterns. Air flow within the bed was obtained from pressure drop gradients, and solid flow was obtained from particle velocity measurements taken at the wall. Pressure drop, air flow distribution between spout and annulus, solid circulation rate and flow line data are summarized. A correlation is proposed which relates pressure drop and particle velocity at the top of the bed with superficial air velocity at air flows above minimum spouting. Particle velocity measurements in the spout were made from photographs, and were calculated approximately from the drag equation for a single particle.
Heats of mixing and vapor‐liquid equilibrium calculations
Authors: Lu Benjamin C.‐Y. 
Published: February 2011

AbstractIn the literature, when the available integrated forms of the Gibbs‐Duhem equation are employed for extrapolating vapor‐liquid equilibrium data at isobaric conditions, the relative partial molal enthalpies at constant liquid compositions, L, are assumed either to be zero or to be independent of temperature. An investigation of the temperature effect on heats of mixing for non‐ideal solutions reveals that these assumptions are invalid and that the quantity L varies linearly with temperature. Therefore the liquid activity coefficients at constant compositions should involve three temperature terms of the form a + (b/T) + c log T for extrapolating purposes. As a result, more general equations are proposed.
Influence of the presence of vapor diffusion from a wetted non‐adiabatic boundary upon the sensible heat transfer between a boundary wall and a gas stream
Authors: Hedlin C. P. , Hooper F. C. 
Published: February 2011

AbstractThe evaporation of a liquid from a wetted surface into a gas stream has consequences which are of fundamental importance in the analysis of sensible heat transfer at the boundary. The presence of a relatively high concentration of vapor in the region adjacent to the surface influences the physical properties of the fluid and the vapor concentration gradient affects the heat transfer mechanism.Experimental equipment was devised to measure the sensible heat transfer coefficients at the inside surface of a porous ceramic tube from which water was being evaporated. Series of tests were carried out for non‐adiabatic wall conditions over ranges of the Reynolds Number from 5,600 to 16,000, tube diameter from 1.360 to 3.300 inches, bulk air temperature from 150 to 220°., and wall vapor pressures from 0.35 to 2.20 p.s.i.a.Over the range of vapor pressures and evaporation rates investigated, the sensible heat transfer coefficients were not observed to depart significantly from those predicted by generally accepted relationships for the dry wall case.
The carbon dioxide‐hydrogen sulphide‐methane system: Part II. Phase behavior at 40°f. and 160°f.
Authors: Robinson D. B. , Lorenzo A. P. , Macrygeorgos C. A. 
Published: February 2011

AbstractThe phase behavior of the carbon dioxide‐hydrogen sulphide‐methane system, previously reported at a temperature of 100°.F.(1), has been investigated at pressures of 400, 1000, and 1600 lb./in.2abs. at 40°F. and at pressures of 1000, 1330 and 1600 lb./in.2abs. at 160°F. Correlation of the experimental data is based upon equilibrium ratios calculated for the individual components, Equilibrium ratios were found to be a function of system composition, temperature, and pressure. Deviation of the liquid phase from ideal solution behavior, as indicated by calculated activity coefficient ratios, is, in general, most dependent upon system composition at the higher pressures and lower temperatures.
Fundamental aspects of solids‐gas flow: Part III. Accelerated motion of a particle in a fluid
Authors: Torobin L. B. , Gauvin W. H. 
Published: February 2011

AbstractAn analysis of the extensive literature on non‐steady drag forces supports the correlation of the data by means of a total drag coefficient, which appears to be a function of the Reynolds Number and of a reduced time parameter which is related to the number of particle diameters traversed since the initiation of the motion. The added mass concept is shown to be both completely inadequate and theoretically unsound. An increase in wake turbulence resulting from Reynolds Number increases or from the occurrence of surface roughness seems to diminish the acceleration effects.Fundamental studies of the flow fields around blunt bodies reveal the extreme complexity of the phenomena occurring during acceleration. Explanations offered for the characteristics of the non‐steady drag coefficient behavior re shown to be frequently at variances with these findings.
The incorporation of fission products into glass for disposal
Authors: Bancroft A. R. 
Published: February 2011

AbstractThere is need of an economical and safe method of disposing of radioactive waste produced by nuclear reactors. A method for the incorporation of fission products into glass is being studied at Chalk River. Class containing up to 50 curies of fission products per kilogram has been made during the investigation of the process. This radioactive glass has been used in stability studies in the laboratory and in the field.Nepheline syenite (a rock containing Na, K and Al silicates) fluxed with up to 30% by weight of lime, is used as the base for the glass. A nitric acid solution of the fission products is added to a pelletized mixture of the solids. When the mixture is heated nitric acid is evaporated near 110°C. The nitrates are decomposed in the temperature range 130–600°, and the mixture is melted to form a glass at a maximum temperature of 1350°. Two of the fission products, ruthenium and cesium, are volatilized to varying degrees from the mixture during heating and create a major contamination and containment problem.The method of processing and results obtained are discussed. The volatilized elements have been removed from the off‐gas stream by a method which permits their incorporation into glass. Scale‐up of the process to treat fission product wastes from power reactors should present no great difficulty other than design of equipment for the remote processing of large quantities of radioactive material at high temperature.
Effect of natural convection on transition to turbulence in vertical pipes
Authors: Scheele George F. , Rosen Edward M. , Hanratty Thomas J. 
Published: February 2011

AbstractThe effect of natural convection on transition to a disturbed flow in a heat transfer section of a vertical pipe has been investigated. The transition is related to the distortions of the velocity profile caused by natural convection. When natural convection is in the direction of forced flow the transition appears to occur through the growth of small disturbances. Transition occurs suddenly when natural convection is opposite the direction of forced flow and it appears to be associated with a separation of the flow at the wall.
Studies of bubble formation and rise
Authors: Poutanen A. A. , Johnson A. I. 
Published: February 2011

AbstractPreliminary to mass transfer studies, studies of bubble shape and area during formation and of velocity of rise after formation were made for nitrogen bubbles in water and two hydrocarbon oils.Bubble profiles were found to fit an empirical equation of the form rnθ = 1 where r and θ are polar coordinates.Quantative studies of bubble volume and area as a function of time are reported.A limited correlation for the velocity of rise of a chain of bubbles in a viscous oil is presented.
Kinetics of the vapor‐phase oxidation of napthalene over a vanadium catalyst
Authors: Shelstad K. A. , Downie J. , Graydon W. F. 
Published: February 2011

AbstractRates of oxidation of naphthalene were measured for the temperature range 300°C. to 335°C. using a thin layer of vanadium oxide‐potassium sulfate‐silica catalyst in a flow reactor. The amounts of naphthalene converted were determined by analysing the products for 1,4‐naphthoquinone, 1,2‐naphtho‐quinone, and phthalic anhydride. Negligible amounts of products of complete combustion were formed.The reaction rate data obtained at low conversions of naphthalene were correlated by the following expression, based upon a model for the reaction proposed by Hinshelwood:

From the results of experiments in which the contact time was varied, it was suggested that the reaction course consisted of two parallel, consecutive reactions in which 1,4‐ and 1,2‐naphthoquinone are intermediates in the formation of phthalic anhydride.
Effect of diesel locomotive operation on atmospheric conditions in a railway tunnel
Authors: Rennie R. P. , Jegier Z. , Katz Morris 
Published: February 2011

AbstractAn extensive study was made over a seven day period to determine if it would be feasible, from an air pollution view point, to operate diesel locomotive powered trains through the St. Clair Tunnel. The test involved the passage of approximately 200 diesel powered freight and passenger trains through the tunnel; 3,000 air samples were taken and measurements were made on air flow and smoke density. Concentrations of carbon monoxide, nitrogen dioxide, total oxides of nitrogen, aldehydes, sulphur dioxide, carbon dioxide and oxygen were determined.The sampling methods, sampling equipment, analytical procedures and test equipment used for this particular investigation should be applicable to a variety of air pollution problems met in the chemical industry.
Heat transfer to a surface reacting fluid in turbulent flow
Authors: Rothenberg Ronald I. , Smith J. M. 
Published: February 2011

AbstractThe effect of chemical reaction on heat transfer has been studied for turbulent flow in tubes of a reacting gas. The analysis is carried out for a heterogeneous, catalytic reaction occurring at the wall surface. Equations are presented for predicting the increase in heat transfer coefficient due to reaction in terms of the rate of reaction, diffusion, and operating conditions. For an exothermic reaction the total heat transfer coefficient is increased when the gas temperature is greater than the wall temperature, and decreased when the gas temperature is less than the wall value. The effect is greatest for rapid reactions; that is, when diffusion of reactants to the tube wall determines the rate of reaction.The equations are applied to the catalytic hydrogenation of ethylene. The results show that the total heat transfer coefficient can be at least ten fold larger than the coefficient for a non‐reacting system at the same flow conditions.In general, the results of this study suggest that a wall‐catalyzed reaction can be an effective means of increasing the heat transfer rate from gases in turbulent flow in tubes. Furthermore, for a porous catalyst applied to the wall, enlarging the thickness of the catalyst layer will increase the effect on the heat transfer rate.
Temperature dependence of the binary diffusion coefficient of gases
Authors: Scott D. S. , Cox K. E. 
Published: February 2011

AbstractThe variation with temperature of the binary gas diffusion coefficient for the gas pairs N2 ‐ H2 and NH3 ‐ H2 is reported for the temperature range of 0°–300°C. The data were obtained using a steady state flow method, and the apparatus and experimental conditions relative to this technique are discussed. Although this method does not give absolute values of the diffusion coefficient, it is relatively simple and accurate.The extent of agreement of the data with equations for the prediction of gas diffusion coefficients is shown. Better results are obtained when these equations are applied to nearly ideal systems, such as the N2 ‐ H2 pair, rather than to gases which have highly polar molecules such as NH3.
Formation and quenching of nitric oxide in a continuous flow furnace
Authors: Mordell D. L. , Thompson A. L. , Yano G. 
Published: February 2011

AbstractA pre‐pilot plant facility for the thermal fixation of atmospheric nitrogen has been successfully built and operated.Gas temperatures exceeding 3000°K. have been reached but the quenching rates available to fix the nitric oxide were found to be inadequate for the gases at these high temperatures. However, yields of 3.7 nitric oxide by volume have been realized experimentally.A separate water cooled sampling probe inserted at the top of the furnace gave quenching rates of the order of 10°C./sec. This also permitted the study of the effect of variation in the quenching rate while maintaining other conditions constant. The oxygen concentration appeared to have less effect than previous results indicated, but this may have been due to uncertainties in estimating gas temperatures near 3000°K.
The development of the alum‐amine process for the recovery of alumina from shale
Authors: Thomas G. , Ingraham T. R. 
Published: February 2011

AbstractBased on a review of the extensive published literature on the recovery of alumina from clays and shale, sufficient experimental work was done on a bench scale to establish a flow sheet whereby these materials might be treated for the recovery of cell‐grade alumina. The significant step in the processing is the recovery of potassium alum, and its purification by either recrystallization or liquid‐liquid extraction.
A spouted mixer‐settler
Authors: Johnston T. R. , Robinson C. W. , Epstein N. 
Published: February 2011

AbstractA new type of mixer‐settler is described wherein the heavy liquid phase is spouted upward through a depth of light liquid phase and allowed to settle below the light phase. The method does not require mechanical agitation, allows both mixing and settling to occur continuously in the same chamber, and is simple in design.Optimum conditions have been determined for bench‐scale extraction of benzoic acid from toluene by means of a water spout. Independent variables studied were water rate, toluene rate, spout pipe diameter and wall effect. Dependent variables measured were spout height, spout spread, initial entrainment points and stage efficiency. Murphree spoutedphase efficiencies up to 96% were obtained.