bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: Polyaniline Nanofibers: A Unique Polymer Nanostructure for Versatile Applications
Authors: Li Dan , Huang Jiaxing , Kaner Richard B. 
Published: March 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Computational Enzymology: Insight into Biological Catalyst from Modelling
Authors: van der Kamp Marc W. , Mulholland Adrian J. 
Published: March 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: One‐Dimensional Self‐Assembly of Planar π‐Conjugated Molecules: Adaptable Building Blocks for Organic Nanodevices
Authors: Zang Ling , Che Yanke , Moore Jeffrey S. 
Published: March 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Development of an On‐Site Measurement System for Salivary Stress‐Related Substances Based on Microchip Capillary Electrophoresis Technology
Authors: Tanaka Yoshihide , Naruishi Nahoko 
Published: March 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Particle motions in sheared suspensions XX: Circular cylinders
Authors: Darabaner C. L. , Raasch J. K. , Mason S. G. 
Published: March 2009

AbstractThe behavior of rigid circular cylinders suspended vertically in viscous fluids in laminar shear flow was found to compare favorably with a theory for infinitely long cylinders which we have extended to include interactions between two cylinders of different diameters. A description of the versatile Couette apparatus in which most of the experiments were performed is included. Observations were made on single cylinders at various distances from the wall bounding flow, on collisions between cylinders of both equal and unequal diameters and on interactions between a cylinder and a sphere. Collision doublets were found to be either permanent or separating, depending on the initial orientations and separations of the particles. The behavior of these particles is analogous to that of spheres in Couette flow.
Surface thermodynamics of liquid mixtures
Authors: Sprow F. B. , Prausnitz J. M. 
Published: March 2009

AbstractThe surface tensions of both simple and complex liquid mixtures are considered. It is shown that the surface tensions of mixtures of simple liquids can be predicted well from a model utilizing the concept of a regular surface solution. For complex mixtures, the use of a parameter reflecting the difference in characteristic energy between the bulk liquid and the surface leads to a good fit of the data for a number of systems.
Kinetic studies of the dissolution of brass
Authors: Ahmed N. , Tinker E. B. 
Published: March 2009

AbstractThe rates of dissolution of 85/15 brass, 70/30 brass, and 60/40 brass in oxygenated dilute hydrochloric acid solution have been measured in the temperature range 25°C to 57°C. In each case the dissolution was found to occur in several distinct stages, described by different rate laws and having different energies of activation. The activation energies indicate that the process is not completely mass transfer controlled. Significant dezincification occurred only in the case of the 60/40 brass. The data indicate that the dezincification occurred through a total corrosion step followed by redeposition of copper. A modification of a mechanism proposed by Habashi(6) is shown to correlate the observed data for monophase brasses.
Approximate solutions of viscous incompressible flow around fluid spheres at intermediate reynoldc's numbers
Authors: Nakano Yoshisuke , Tien Chi 
Published: March 2009

AbstractApproximate solutions of viscous incompressible flow around fluid spheres were presented. Expressions for stream functions approximately satisfying equations of motion for both exterior and interior fluid were obtained using Galerkin's method with the inclusion of inertial terms for both equations. The retention of inertial terms of the interior fluid was found to have insignificant effect on the flow behavior of exterior fluid. However, the circulation velocity within the fluid sphere was found to increase with the increase of the internal Reynold's number, which may be of importance to the study of mass transfer within fluid spheres.
An experimental study of mass transfer with chemical reaction from single gast bubbles
Authors: Johnson A. I. , Hamielec A. E. , Houghton W. T. 
Published: March 2009

AbstractRates of forced convection mass transfer from single bubbles of carbon dioxide reacting in aqueous ethanolamine solutions have been determined experimentally for intermediate babble Reynolds numbers.A water tunnel apparatus, and technique for measuring mass transfer rates are described.The results of the experimental study are compared with a mathematical model describing mass transfer with an accompanying second order reaction; the hydrodynamic condition of the model is described using Kawaguti type velocity profiles.The experimental data appear to confirm the model satisfactorily.
Recent developments in plasma jet technology
Authors: Kubaisek G. R. , Gauvin W. H. 
Published: March 2009

AbstractThis article is an up‐to‐date survey of the field of plasma jet technology. Its intention is to make available the latest information about the characteristics, limitations and applications of plasma generating devices, particularly in the field of chemical processing.The uses of plasma jet in the aerospace field, and in material processing and fabrication are briefly reviewed. The chemical applications discussed include the syntheses of acetylene, cyanogen, nitric oxide, as well as various carbides and nitrides.
Wall mass transfer in liquid‐fluidized beds
Authors: King D. H. , Smith J. W. 
Published: March 2009

AbstractIonic mass transfer coefficients between the wall and a liquid fluidized bed of 0.043 inch lead glass spheres have been measured using the diffusion controlled reduction of ferricyanide ion at a nickel cathode.The coefficients obtained are correlated in terms of the dimensionless j factor and are compared with dissolution mass transfer results by this author and with a recent liquid fluidized bed heat transfer study(1) with these same particles. It is concluded that in the dissolution study either mechanical erosion or roughness effects or both were present. No analogy was found to exist between overall heat and mass transfer in a liquid fluidized bed in which there is a large difference between the Schmidt and Prandtl numbers because the dominant resistance is different for the two cases.
The thermal theory and the plate efficiency
Authors: Ruckenstein E. , Smigelschi O. 
Published: March 2009

AbstractAn experimental study concerning the plate efficiency is performed in bubbling regime and in foam regime, by means of a single tray column. Two mixtures have been used. One of them, the system cyclohexane‐toluene was selected since its surface tension is practically independent of concentration, while the other system (methanol‐water) was selected because its surface tension depends strongly on concentration.For the bubbling regime, experiments lead to the conclusion that the plate efficiency depends in the same manner for both mixtures on composition (the curves of efficiency vs. composition present a weak maximum) though the Marangoni effect does not occur for the first system and has favorable conditions of occurrence for the second system.For the foam regime the efficiency is practically equal to unity for all compositions.In the theoretical part of the paper several possible mechanisms of the rectification process are discussed. One is based on the diffusional model derived from the classical theory. Three other equations are based on the assumption that vaporization in the bulk of the liquid occurs too. A criterion for the occurrence of this thermal effect is given.A possible explanation of the non‐occurrence of the thermal effect in cases for which the above mentioned criterion leads to a contrary conclusion, is also included.
Modelling polymerization reactors with applications to optimal design
Authors: Ray W. H. 
Published: March 2009

AbstractUsing generating functions, models for polymerization reactors are developed without using kinetic approximations. One of the models is then used for the optimization of a series of tank reactors in which free radical polymerization is taking place. It is found that peak‐seeking methods are a convenient and efficient method of optimizing such systems. Curves showing “optimal” design alternatives are generated for the simple example treated.
Holdup and flooding in air liquid mixing
Authors: Rushton J. Henry , Bmbinet Jean‐Jacques 
Published: March 2009

AbstractThe amount of flowing air held up, or retained, under the surface of water and corn syrup solutions was measured in cylindrical tanks of different sizes using turbine type mixing impellers. Holdup is frequently used as an index of the effectiveness of gas‐liquid contacting in adsorption or stripping operations; it can be correlated with air flow rate and power input as followsh = a(PT/V)bFcwhere h is the holdup of air in ft. per ft. of ungassed liquid, a, b, and c, are constants, (PT/V) is the total power supplied by the impeller and air per unit volume, and F is the superficial velocity of the air. Values of a and b vary with tank size. The effect of liquid viscosity is pronounced but not amenable to simple correlations with the constants.Limits of operation to prevent flooding are defined as functions of impeller power and air flow.
Drag coefficients of evaporating spheres in a turbulent air stream
Authors: Clamen A. , Gauvin W. H. 
Published: March 2009

AbstractA study was made to determine the effect of mass transfer on the drag coefficients of freely‐moving aerodynamically smooth spheres, accelerating in a co‐current turbulent air stream. The particles consisted of celite impregnated with liquid sulphur dioxide and varied in diameter from 0.184 to 0.989‐inch. Accurate time‐distance data were obtained with a new particle‐tracking technique which allowed the quantitative measurement of drag coefficients for relative turbulence intensities varying from 5 to 30%.The range of Reynolds numbers studied was from 2100 to 29,800, which, because of the effect of free‐stream turbulence, forms a part of the super‐critical flow regime. The results have thus been compared with the previously reported drag data for solid non‐evaporating spheres in a similar flow region.Mass transfer was found, in general, to decrease the super‐critical drag on a sphere and to reduce the influence of relative turbulence intensity. This alteration in momentum transfer is probably due to a reduction in the skin friction and to a pressure increase in the wake of an evaporating sphere.
Particle retardation in vertically oscillating fluids
Authors: Houghton Gerald 
Published: March 2009

AbstractAn analytic expression has been deduced for the ultimate velocity of a free particle in a vertically oscillating fluid by evaluating asymptotic forms of Floquet's solution to the Mathieu equation arising from the nonlinear Langevin equation describing the particle‐fluid interactions. Using general Mathieu theory it has been rigorously demonstrated that directional particle motion in a gravitational field can be retarded by sinusoidal fluid oscillations when the particle‐fluid drag law is of square form. The earlier Rayleigh‐Ritz approximation (Houghton 1966) for the retarded particle velocity is shown to be in good agreement with the results of Mathieu theory, as summarized in graphical form.
Thermodynamic functions for 3‐fluoropropene
Authors: Bryce H. W. , Lielmezs J. 
Published: March 2009

AbstractThermodynamic functions Cp°, S°, (H°‐H0°)/T, —(F°‐H0°)/T have been calculated for 3‐fluoropropene in the ideal gas state from 298.15° to 800°k. at 1 atm. pressure. The restricted rotational contribution has been treated by the conventional method of Pitzer and Gwinn.
Behavior of gas bubbles in vertically vibrating liquid columns
Authors: Rubin Eliezer 
Published: March 2009

AbstractA theoretical analysis of the behavior of gas bubbles in vertically vibrating liquid columns is presented. The theoretical approach predicts the depth in liquids at which the downwards force, due to vibrations, acting on single bubbles just balances the buoyancy force, i.e. the depth of no net movement of given bubbles. Theoretical results predicting the direction of movement of bubbles were obtained for various diameters over a wide range of frequencies, amplitudes, liquid viscosities and densities. Agreement with published experimental work is good.
Distribution of lengths in the breakage of fibres or linear polymers
Authors: Goren Simon L. 
Published: March 2009

AbstractThe distribution of fiber or polymer lengths during breakage is considered. It is shown that under certain conditions the distribution of lengths is given by a self‐preserving form which is independent of the initial distribution and is not explicitly dependent on time. Some self‐preserving distributions are calculated. The theory is compared with an experiment on the breakage of glass fibres caused by milling.
Quasilinearization technique for solution of boundary layer equations
Authors: Lee E. S. , Fan L. T. 
Published: March 2009

AbstractOwing to the split boundary conditions, there arise many difficulties in solving numerically the nonlinear equations describing the boundary‐layer flow. It is shown in this paper that the quasilinearization technique is a useful tool for solving the ordinary differential equations, which are obtained from the boundary layer equations through a similarity transformation. With very approximate initial guesses, only four to six iterations are needed to obtain a five digit accuracy.
Flow of suspensions in pipelines(Part 2: Two Mechanisms of Particle Suspension)
Authors: Shook C. A. , Daniel S. M. , Scott J. A. , Holgate J. P. 
Published: March 2009

AbstractThe distribution of sand and nickel particles with height in a horizontal channel of rectangular cross section has been measured and eddy diffusivities have been computed from these measurements. Turbulent suspension of particles appeared to occur where the concentration of solid particles was low, the particle diameter was small (< 0.2 mm.) and the ratio of the settling velocity of the particles to the friction velocity of the flow was less than 0.2. Where these criteria were not satisfied, concentration profiles were observed to deviate significantly from the shape associated with turbulent suspension. These deviations are attributed to the effect of particle interactions investigated by Bagnold.
Solve at extraction in an air‐pulsed packed column
Authors: Baird M. H. I. , Gloyne A. R. , Meghani M. A. N. 
Published: March 2009

AbstractA novel type of extraction column has been constructed in which liquid pulsations are produced without the need for any mechanical moving parts. The factors governing the frequency and amplitude of the pulsations are discussed briefly. The effects of pulsation upon the extraction of acetic acid from kerosene by water in a packed column have been measured. The pulsations increase the number of transfer units by as much as threefold, a result similar to the observations of previous workers who used conventional pulsators having moving parts.
Dynamic response of a double effect evaporator
Authors: Andre H. , Ritter R. A. 
Published: March 2009

AbstractThe open loop dynamic response of a laboratory scale double effect evaporator has been adequately described by a simple mathematical model based on the unsteady state material and energy balances associated with the various elements of the system. Excellent agreement has been achieved between the experimentally determined response of the evaporator to large disturbances in steam rate and feed rate and the predicted response based on the digital computer solution of the non linear model.
Motion of continuous surfaces through stagnant viscous non‐Newtonian fluids
Authors: White James Lindsay 
Published: March 2009

AbstractAn analysis is given of the hydrodynamics and drag of a rigid sheet moving through a stagnant non‐Newtonian fluid. The methods of boundary layer theory are applied and it is shown that a ‘similarity’ transformation is sometimes possible. The effect of the apparent viscosity on the velocity field and drag is discussed and detailed solutions for different non‐Newtonian viscosities are obtained by integral momentum methods. The problem of drawing a cylinder through a non‐Newtonian fluid is also discussed.
The ratio of terminal velocity to minimum fluidising velocity for spherical particles
Authors: Bourgeois P. , Grenier P. 
Published: March 2009

AbstractThe analogy between the states of a particle falling at its terminal velocity in a fluid and that of a particle in a bed, at incipient fluidization by the same fluid, suggests the possibility of a correlating minimum fluidizing and terminal velocities and of predicting the minimum fluidizing velocity. A semi‐theoretical curve has been obtained, relating (Ret/Remf) to Fn = gpF (rHS – rHF) d3/μ2 and it has been compared with new experimental data collected for this purpose in the range 103<Fn<108. Analytical expressions for (Ret/Remf) are proposed.
Dependence of electrostatic charging currents on fluid properties
Authors: Goodfellow H. D. , Graydon W. F. 
Published: March 2009

AbstractThe dependence of the electrical charging of hydrocarbons on the chemical nature of non‐hydrocarbon additives has been investigated. An improved apparatus and technique allowed the authors to obtain data for new fluid systems over a wide range of solution conductivities and flow velocities. Currents and voltages have been measured from insulated stainless steel tubes, for different concentrations of polar species in hydrocarbon solutions, for Reynolds numbers of 1800 to 35,000.Recent electrification theories explain the charging process on the basis of a diffusion‐controlled process. The magnitudes of the charging currents can be predicted using the usual mass transfer analogies. Experimental results, obtained for different polar additives studied, agreed with the theory. The sign of the measured current is not predicted theoretically. Potentials of both signs are observed. The particular sign obtained seems to be determined by the chemical nature of the polar additive. Different additives of similar chemical structure all give one sign.
The Electrolytic “Sintering” of Nickel Powder
Authors: Henderson I. H. S. , Ladan S. G. 
Published: March 2009

AbstractAdherent and coherent deposits of nickel sponge similar to sintered nickel may be made from sulphate, chloride, fluoborate or sulphamate nickel plating solutions containing nickel powder in suspension, providing the concentration of free acid is maintained sufficiently high to inhibit co‐depesition of Ni(OH) In nitrate solution, cathodic reduction of nitrate and deposition of Ni(OH)2 predominates.
On the relation between state and adjoint variable initial conditions in optimum control theory
Authors: Latour Pierre R. 
Published: March 2009

AbstractThe algebraic relation between state and adjoint variable initial conditions for time‐optimum control of a particular second order linear system is reported. The relation between adjoint initial conditions and switching time suggests that difficulties might arise when boundary‐value search methods are employed to solve two‐point boundary‐value problems. These analytical results support the conclusions in a recent paper by Paynter and Bankoff.
Reactor dynamics and molecular weight distributions: Some aspects of continuous polymerisation in tubular reactors
Authors: Cnitron‐Cordero R. , Mostello R. A. , Biesenberger J. A. 
Published: March 2009

AbstractA study was made of the effect of residence time distribution and thermal nonuniformities on molecular weight dispersion in continuous nonchain and chain polymerizations, respectively. The analyses were conducted with the aid of the assumption of microsegregation, which facilitated and unified the computational approach.Holdback was examined and found to be a good criterion for characterizing the importance of residence time distribution. Power‐law flow index was found to have a direct effect on molecular weight dispersion in isothermal nonchain polymerizations as well as an indirect influence in chain polymerizations via its role as a parameter for thermal sensitivity.It was concluded that the isothermal, segregated, continuous stirred tank reactor has a greater effect on molecular dispersion in nonchain‐type polymerizations than the worst isothermal tubular reactor, as correctly predicted by holdback, and temperature nonuniformities have a profound influence on molecular dispersion in chain‐type polymerizations.
Interpretation of methane adsorption on activated carbon by nonisothermal and isothermal calculations
Authors: Lee Robert G. , Weber Thomas W. 
Published: March 2009

AbstractExperimental breakthrough curves for methane absorption on activated carbon are analyzed using isothermal and nonisothermal models. Interaction of heat and mass transfer effects vary from being almost negligible to being quite pronounced. Some rather large radial temperature gradients were measured in the bed. In spite of these, the fit of the experimental data to the nonisothermal model is reasonably good. Stability problems in the nonisothermal solution are discussed.
Stereophotogrammetry in particle‐flow investigation
Authors: Reddy K. V. S. , Van Wijk M. C. , Pei D. C. T. 
Published: March 2009

AbstractStereophotogrammetry was used for the first time to measure the local particle velocity vector and its turbulent components in two‐phase solid‐gas flow in a 10 cm. I.D. vertical pipe. From the image counts on the stereophotographs, it has also been demonstrated that the stereophotogrammetry could be used for the direct determination of the radial concentration distribution of the particles in the pipe.
The effects of changes in problem parameters on chemical equilibrium calculations
Authors: Smith W. R. 
Published: March 2009

AbstractA simple method is described for evaluating the first order changes in calculated chemical equilibrium compositions resulting from changes in the problem parameters of temperature, pressure, initial reactant compositions, and standard free energy data for the species. It may be used to calculate the first order derivatives of the equilibrium mole numbers with respect to the problem parameters, thus indicating the solution's sensitivity to small changes in these values. Using the temperature and pressure derivatives and appropriate data for the species, all first order thermodynamic derivatives of the equilibrium mixture properties may be calculated. Finally, surveys may be performed of the equilibrium system for ranges of the problem parameters. The technique involves the solution of a set of m + ϕ linear equations, where m is the number of elements and ϕ the number of phases.