RESEARCH RESULTS . . . immediate& available All papers listed are being considered for publication in I&EC or one of the I&EC Quarterlies. They are available in manuscript form, with the requirement that any reference to their content in a publication must have the author's prior approval. Orders are processed within 24 hours of receipt, with shipment b y first class mail. Prices for I&EC subscribers and nonsubscribers are listed with each manuscript. Please include payment with order.
Kinetics of Formation of Hydrogen Cyanide from Methane and Ammonia in a Microwave Plasma. A first-order kinetic model describes the formation of HCN a t pressures from 10 to 25 torr, using a 2450 mHz frequency. Theory of diffusion controlled discharge operation results in constant E/p and average electron energy at a given pressure.
Strategy of Time Optimal Control b y linear Programming. For a linear discrete system, we accomplish the strategy of time optimal control system and combine regulator and servo problems into a single one. An iterative scheme is proposed to generate the optimal control policy by upper-bound algorithm of linear programming and an illustrative example is calculated in detail.
T . Juul-Dam, N . F. Brockmeier, The University of Texas Ms. 6 9 - 3 6 9 4 5 pages (1 2 figures, 2 tables) I&EC Subscribers $1 0.00 Nonsubscribers $20.00
Yung-Cheng Chao, Hsiu-Hsyong Hsu, National Taiwan University, Taipei, Taiwan, China 2 2 pages (4 figures, 6 tables) Ms. 6 9 - 3 0 9 I&EC Subscribers $6.00 Nonsubscribers $1 2.00 Making the Most of a "One-Shot'' Experiment An experimental investigation of a plant process is often necessarily limited to a few test runs to avoid undue production loss. By careful choice of experimental strategy and thorough data analysis procedures, even such a "one-shot" effort can yield fruitful results.
Statistical Characteristics of Thin, Vertical Wavy liquid Films. Reports probability distribution of liquid height, wave celerity, base dimension, wave spacing, amplitude, pressure spectra and presents a method for extracting wave shape from fluctuating signals. Liquid flow ranged to Reynolds numbers of 6000, with varying degrees of interfacial shear.
David W . Bacon, Du Pont of Canada 2 4 pages (3 figures, 3 tables) Ms. 6 9 - 3 3 1 I&EC Subscribers $6.00 Nonsubscribers $1 2.00
A . S. Telles, and A. E. Dukler, University
OJ
Houston
Ms.69-380 5 8 pages ( 2 4 figures, 1 table) I&EC Subscribers $1 2.00 Nonsubscribers $24.00
Investigation of Steam Condensing on Vertical Rows of Horizontal Corrugated and Plain Heat transfer data on copper and Tubes. cupronickel tubing a t various levels of condensing temperature, water velocity, and log mean temperature difference are analyzed. Design correlations are presented, and the benefits of corrugated tubing in water desalting plants are illustrated.
Axial and Radial Mixing in a Concurrenl Bubble Column. Mixing for air-water system investigated by steady-state tracer injection. Peculiar upstream concentration profiles observed. Backmixing is excessive. Dispersion coefficients and their radial variation estimated by axial dispersion model. Mixing increases with gas flow in a specified manner.
James G. Withers, Uniuersal Oil Products Comfiany; Edwin H. Young, The University of Michigan Ms. 69-351 4 0 pages (20figures, 5 tables)
National Research Center, Cairo, Egypt, United Arab Republic Ms. 6 9 - 3 9 8 2 7 pages ( 8 figures, 2 tables) I&EC Subscribers $6.00 Nonsubscribers $1 2.00
R E C Subscribers $8.00
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A Continuous Process for the Manufacture of Polyester l i r e Yarn from Terephthalic Acid. The production of high intrinsic viscosity polyester in liquid state offers technical and economical advantages, especially in combination with direct spinning. T h e high pressure spinning process allows minimum polymer degradation and maximum stretchability of the spun yarn.
Heimo Hardung-Hardung, Germany
Ms. 6 9 - 3 5 2 I&EC Subscribers $2.00
Vickers-Zimmer
AG,
8 pages Nonsubscribers $4.00
Coproduction of Trichloroethylene and Perchloroethylene b y Ethylene Process. Ethylene is converted to the chlorinated ethanes in the absence of catalysts. T h e mixture of CzHzClr and CzHCk is cothermally cracked. The process is simple, the production ratio of CHCl = CClz to CCIz = CClz is variable.
Takeo Kawaguchi and Yoshitaka Suzuki, Tao Gosei Chemical Industry Co., Ltd., Japan MS.6 9 - 3 6 1 2 5 pages ( 2 4 figures) I&EC Subscribers $8.00
134
IVilliam B. Krantr and Simon L. Goren, Unioersity of CaliJornia, Berkeley Ms. 6 9 - 3 9 9 4 3 pages (1 2 figures, 3 tables) I&EC Subscribers $1 0.00 Nonsubscribers $20.00 A N e w Process for Production of Tetrahydrofuran. A direct hydrogenation process using maleic anhydride as raw material. I n this paper the kinetic study is described and some pilot plant data are given.
Junichi Kanelaka, Taisuke Asano, and Shinobu Masamune, Mitsubishi Petrochemical Company, Ltd., Japan Ms. 6 9 - 4 0 0 3 4 pages (1 1 figures, 6 tables) I&EC Subscribers $8.00
Nonsubscribers $ 1 6.00
A Generalized Theory for Fluidized Bed Coating, Proposes a n exact theory to predict rate of dip coating in a fluidized bed of polymeric powders. Solutions involve the well-known Pohlhausen integral method for laminar boundary layers. Equations for coating thickness produce results in agreement with experiments.
M . Elmas, Universiv of Delft, Holland Ms. 69-401 18 pages (5 figures) I&EC Subscribers $4.00
Nonsubscribers $8.00
S. Eissa, :M. IM. El-Halwagi, and M. A . Saleh,
A Coating Theory in a Dense Fluidized Bed. Proposes a theory to predict coating rate. Equations for coating thickness involve physical and thermal properties of fluidizing medium
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Experimental Study of Stability of Thin liquid Films Flowing Down a Plane. Measurements of wave velocities, wave lengths, and amplification factors for imposed disturbances of controlled frequency and amplitude are compared with existing theories.
:HEMISTRY
polymer powder, object to be coated, and bed as a whole. Experiments are in good agreement with theory.
M . Elmas, University of Delft, Holland
MS.69-402 I&EC Subscribers $8.00
32 pages (1 3 figures) Nonsubscribers $1 6.00
A Theory of Coating with Objects Being Heated in Fluidized Bed. Proposes a general theory to predict coating rate. Equations involve physical and thermal properties of the whole system. Theory can be used in predicting coating rate of a continuously moving (or stationary) object being heated in the bed.
M . Elmas, University of Delft, Holland MS.69-403 13 pages (4 figures) I&EC Subscribers $4.00 Nonsubscribers $8.00 Viscous Flow Through Particle Assemblages at Intermediate Reynolds Numbers-SteadyState Solutions for Flow Through Assemblages of Cylinders. Reynolds numbers to 500 were investigated, and cylinder interaction was accounted for, using a “surface-interaction model.” Numerical results are presented and compared with experiment in the form of surface vorticity and pressure distributions, and form, friction, and total drag.
B. P . LeClair and A . E. Hamzelec, McMaster University, Canada Ms. 69-409 28 pages (5 figures, 1 table) I&EC Subscribers $6.00 Nonsubscribers $1 2.00 Continuous Thickening of Flocculated Suspensions: Comparison with Batch Seeling Tests and Effects of Floc Compression Using Pyrophyllite Pulp. Slow stirring in batch tests found to give closer agreement to continuous thickener behavior. Evidence of mechanical compaction presented and used to confirm generalized theory of sedimentation and compression of flocculated pulps employing the concept ofJqoc volume concentration.
Keith J . Scott, S. A . Council for Screnttfic and Industrial Research, Pretoria, South Africa Ms. 69-410 23 pages (6 figures, 2 tables) I&EC Subscribers $6.00 Nonsubscribers $1 2.00
Solutions of Viscoelastic Flow Problems in Convected Coordinate Systems. Sometimes i t is convenient to solve flow problems in convected coordinate systems. This method is similar to the Langrangian approach in hydrodynamics. Principles of the method are presented. Solutions of some flow problems of viscoelastic liquids are examined.
H . Rubin, Israel Institute of Technology, Haifa, Israel MS.69-4 14 17 pages I&EC Subscribers $4.00 Nonsubscribers $8.00
Mass Diffusion in Turbulent Flow of Dilute Polymer Solutions. Quantitative estimation of mass diffusion in turbulent flow of drag reducing polymeric solutions is suggested. I t was found that friction coefficient decrease by polymeric additives is associated with a decrease in Sherwood number and Stanton number of the flow.
H. Rubin, Israel Institute of TechnoZogy, Haifa, Israel MS.69-415 l&EC Subscribers $4.00
19 pages (7 figures) Nonsubscribers $8.00
Heat Transfer Mechanism: A Boundary Surface to a System of Particles in Motion In a Gas Stream. Hlgh speed photography provides particle motion information used in model proposal. Calculations compare well with observations for fluidized, pulsed, and moving beds.
Masaru Kobayashi and W. T. Brarelton, Northwestnn University MS.69-416 31 pages (7 figures, 2 tables) l&EC Subscribers $8.00 Nonsubscribers $1 6.00 Applied Research in Glass Melting. Presents trends in fuel consumption per ton glass melted and furnace capacity per day from constant attention to details of operation through applied research information, combustion methods are discussed.
J . C. Hamilton, Owens-Illinois MS.69-417 31 pages (1 7 figures) I&EC Subscribers $8.00
Nonsubscribers $1 6.00
Optimal Control of Plug Flow Heat Exchanger with Control-Produced Either Wall Flux or
Woll Temperature. The technique presented in a companion paper (Ms. 69-412) is applied. Necessary conditions are Fredholm integral equations of the second kind. Both analytical and numerical solutions are presented. A suboptimal control is also given.
Wzlliam A . Weigand, Purdue University 34 pages (8 figures, 7 tables) MS.69-41 1 l&EC Subscribers $8.00 Nonsubscribers $1 6.00 Optimal Control of Linear Distributed Parameter Systems. Presents a technique which avoids the two-point boundary value problem for open loop control. State and control must be related by bounded linear operator. Necessary condition is a linear operator equation.
William A. Weigand, Purdue University MS.69-412 15 pages I&EC Subscribers $4.00 Nonsubscribers $8.00 Kinetics of High-Temperalure Pyrolysis of Propylene, Rates of propylene decomposition and product formation in the 850’ to 1050’ C. range were studied in an annular flow reactor with conversions a t or below 5%. Results were fitted to Arrhenius rate expression.
Joseph A . Sims, Lester S. Kershenbaum, and Jayant Shroff, Drexel Institute of Technology Ms. 69-41 3 29 pages (6 figures, 2 tables) I&EC Subscribers $6.00 Nonsubscribers $1 2.00
Preparation, Properties, and Applicalion of Nylon 12. All three aspects of nylon 12 depend largely on the low water uptake of monomer and polymer. Reformation of oligomers, viscositymolecular weight relationship, and molecular weight distribution are discussed.
W. Griehl and D. Riistem, Emser Werke AG, Switmland MS.69-41 8 22 pages (7 figures, 1 table) I&EC Subscribers $6.00 Nonsubscribers $1 2.00
dispersed phase, and a surface active agent depends on whether or not these substances spread on the water surface.
Ftimitake Yoshida and Tsuneo Yamane, Kyoto University, Japan Ms. 69-428 26 pages (1 1 figures, 2 tables) I&EC Subscribers $6.00 Nonsubscribers $12.00
A Mathematical Model for Continuous Surpension Vinyl Chloride Polymerization in a Series of Stirred Reactors. An empirical kinetic equation for industrial batch suspension PVC manufacture was developed and extended to include continuous processing in a series of stirred reactors. Temperature, catalyst concentration, holdup time, number of reactors, and nonideal mixing were parameters.
J . W. Lacksonen and R . E. Barsan, General Tire d R u bber Go. MS.69-429 12 pages (1 table) I&EC Subscribers $4.00 Nonsubscribers $8.00 O n Kinetic Expressions for Reaction Rate in Noncatalytic Solid-Gas Systems. Continuous kinetic expressions used in gas-solid reactions are analyzed. Strong dependence on pore structure is shown. Two pore structure models are compared. Kinetic expressions having reaction order with respect to solid reactant equal or greater than one are evaluated.
R. E. Cunningham and A . Calvelo, Universidad Nacional de La Plata and Laboratorio de Ensayo de Materiales e Investigaciones Tecnologicas, La Plata, Argentina MS.69-430 7 pages (1 figure) I&EC Subscribers $2.00 Nonsubscribers $4.00 Solution of Combined Convection and Radiation Heat Transfer from Longitudinal Fins of Arbitrary Cross Section. Solutions for temperature distribution, apparent emittance and efficiency of triangular, parabolic profile fins with base and neighboring fin interaction are given.
P. B. Carter, Jr., and Walter Frost, University
of Tennessee Space Institute MS.69-435 50 pages (1 3 figures) I&EC Subscribers $1 0.00 Nonsubscribers $20.00
Reduction of Bismuth Oxide by Carbon Monoxide. T h e rate of reduction of BizOa by C O was measured for several temperatures and reaction times. After the reduction was -]/a complete, the rate was limited by CO and COz diffusion through the layer of bismuth product.
R. F. Bradley, E. I. du Pont de Nemours d Go. MS.69-436 12 pages (8 figures) l&EC Subscribers $4.00
A Process for Butadiene Manufacture by the Catalytic Oxydehydrogenalion of Butenes. A substantial multitubular pilot plant reactor and its supporting recovery system were operated continuously to produce a C4 mixture containing 50 to 60% butadiene. Alternative reactor systems were tried. Coproducts were identified and simple recovery and purification techniques developed.
F. C. Newman, B P Chemicals Ltd., Hull, England Ms. 69-419 19 pages (5 figurer, 5 tables) I&EC Subscribers $4.00 Nonsubscribers $8.00
Oxygen Abrbrption into Oil-in-Water Emulsions in an Agitated Vessel-A Study on Hydrocarbon Fermentors. How kLa for oxygen absorption into water varies with addition of kerosine, liquid paraffin, toluene, oleic acid as the
Nonsubscribers $8.00
Ligand Factors in the lsomerlzalion of Olefins by Palladium Complexes. Study of double bond isomerization of 1-hexene in methylene chloride catalyzed by series of 1,3-dichloro-2-hex-lene-4(p-Z-pyridine N-oxide) -palladium(II) complexes has shown that olefin isomerization results when N-oxide ligand dissociates from original palladium-olefin complex.
W m . H. Clement and Thomas Speidel, Ithaca College MS.69-438 18 pages (4 figures) I&EC Subscribers $4.00 Nonsubscribers $8.00 O n Nucleation Phenomena and the Metartable States of Marter-Precipitation of Slightly Soluble Salts. Nucleation and crystallization are studied by precipitation methods. Some 30 phenomena are observed. Despite high supersaturation no spontaneous nucleation is ob-
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Cambridge Instrument Co.. Fredlen Advertising Chemical Engineering Catalog. Persons Advertising, Inc.
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French Oil Mill Machinery Co.. Central Advertising Agency, Inc.
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7
Polaroid Carp.. Ingalls Associates
2 133
US. Peroxygen Div. of Argus Chemical
Carp., Sudsidiary of Witco Chemical .......................... Geer, DuBois & Co., Inc.
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Tadeusz Adamski, Polish Academy of Sciences, Poland MS.6 9 - 4 3 9 2 6 pages ( 9 figures, 4 tables) I&EC Subscribers $6.00
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Use of the Diaphragm Cell at Elevated Temperatures. Modified form of diaphragm cell suitable for use at elevated temperatures used to measure diffusion coefficients in acetone-benzene system. Measurements show that present methods for predicting temperature varitation of diffusion coefficients are inadequate.
C. J . D . Fell and H . P . Hutchison, University of Cambridge, England MS.6 9 - 4 4 1 21 pages ( 3 figures) l&EC Subscribers $6.00 Nonsubscribers $1 2 . 0 0 The Use of Transition Metal Complexes as Selective Hydrogenation Catalysts. Explores in detail the selective nature of hydrogenation reactions using homogeneous transition metal catalysts. Presents applications of selective catalytic hydrogenations to a variety of areas of iynthetic organic chemistry and discusses mechanistic detail for each catalyst system. 103 referznces.
James E. Lyons, Leonard E. Rennick, Sun Oil Combany; John L. Burmeister, Untversttj 01 Delaware
Ms. 6 9 - 4 5 5 55 pages (1 1 figures, 2 tables) IKEC Subscribers $1 2.00 Nonsubscribers $1 4.00 Indentation Hardness and Practical Properties of Rigid Thermoplastics. Correlates common indentation hardness tests (Barcol, Brinnell, Rockwell, Shore) on rigid thermoplastics, permitting Easy conversion from one scale to another. Also demonstrates good correlation between indentation hardness, ultimate elongation, flexural modulus, flexural strength, and coefficient of thermal expansion.
Rudolph D . Deanin, Gerald F. Sullivan, Dennis J. Doyle, Richard A . Granoff, Lowell Technological Institute, Arthur J . Karstes, DeBell €8 Richardson, lnc. Ms. 6 9 - 4 4 9 1 3 pages (1 2 figures, 1 table) I&EC Subscribers $4.00 Nonsubscribers $8.00 Amine and Ammonium Silicates. I. A N e w Class of Crystalline Soluble Silicates. Crystalline, water-soluble double silicates containing alkali metal and quaternary ammonium ions have been prepared and characterized. These silicates can contain sodium, potassium, or lithium ions in combination with a number of quaternary ammonium ions.
Helmut H. Weldes, Philadelphia Quartz Company 3 5 pages ( 3 figures, 6 tables) Ms. 6 9 - 4 5 0 I&EC Subscribers $8.00 Nonsubscribers $1 6.00
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Japan Sumio Oka International Media Representatives Lid., 1, Shiba-Kotochiracho, Minatok;, Tokyo.
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served. Nucleation by single, foreign, polyvalent ions a t concentrations of 10-s to 10-15 is deduced.
INDUSTRIAL A N D ENGINEERING
Amine and Ammonium Silicates. II. Amine Silicate Solutions. Describes preparation and properties of stable aqueous amine silicate solutions. An ion exchange method was developed to prepare amine silicate solutions from such water-soluble amines as alkyl amines, alkanol amines, and cyclic amines.
solutions by a simple ion exchange method. T h e mole ratio range of these ammonium silicates is between 2 and 6 SiOz/(NHa)zO.
Helmut H. Weldes, Philadebhia Quartz Company MS.6 9 - 4 5 2 1 2 pages (7tables) l&EC Subscribers $4.00 Nonsubscribers $8.00 Coal Char Gasification in a Continuous Electrofluid Reactor. A 12-inch diameter repeats from title reactor was built to investigate production of synthesis gas from coal char and steam. Operation of the system is discussed and progress to date is reported.
Justin L. Beeson, Allen H. Pulsger, and Thomas D . Wheelock, Iowa State L'niveristy ME.6 9 - 4 5 6 2 9 pages (8 figures, 3 tables) I&EC Subscribers $ 6 . 0 0
Nonsubscribers $1 2.00
Heat Exchanger Modeling b y ConservativeScalar Pulse Testing. Reliable dynamic models derived for complex-geometry (helical coil) heat exchangers. Models were formulated from exchanger construction details and from experimental data for salt-tracer pulse tests as steady-state heat transfer studies.
C. J . Messa, G. W . Poehlein, A . S. Foust, Lehigh University MS.6 9 - 4 6 0 2 4 pages (1 1 figures, 2 tables) I&EC Subscribers $6.00
Nonsubscribers $1 2.00
The Condensation of Aluminum Chloride in a Surface Condenser. Overall heat transfer coefficients lay in the range 0.3-0.4 b.t.u./hr.sq. ft.--OF and were dependent upon the intensity of vibration used to shake the condenser walls.
Frank R. Jorgensen, C S I R O , Port Meloburne, Australia MS.6 9 - 4 6 2 10 pages ( 3 figures) I&EC Subscribers $2.00
Nonsubscribers $4.00
Comparisons of Analogous Brominated and Chlorinated Reactive Intermediates in Fire Retardant Polyesters. The effectiveness of bromine us. chlorine has been determined for several halogenated fire retardant polyester intermediates. New polyesters were prepared from 1,4,5,6,7,7-hexabromo-(2,2,1)-5-heptene-2, 3-dicarboxylic anhydride, and 1,4,5,6-tetrabromo-7-oxo-~-norbornene-2,3-dicarboxylic anhydride dimethyl acetal.
J . A. Schnerder, R. G. Pews, and J . D . Herring, The Daw Chemical Company MS.6 9 - 4 6 6 1 6 pages ( 6 tables) I&EC Subscribers $4.00 Nonsubscribers $8.00 The Optimization of linear Fixed-Bed Separations. Formulation of a general principle for optimizing fixed-bed separations is discussed. Application to purification of uremic lymph shows that increasing speed of separation might be a more practical objective than maximizing the sharpness of the effluent curves.
David 0 . Gooney, Clarkson College of Technology
M ~6.9 - 4 6 8 l&EC Subscribers $4.00
1 4 pages (4 figures) Nonsubscribers $8.00
Gas Holdup in Sparged Vessels.
Fractional
00 -
hold-up
where a method for calcu-
E =
l + %
Helmut H . Weldes, Philadelphia Quartz Company MS.6 9 - 4 5 1 15 pages ( 2 figures, 1 table) I&EC Subscribers $4.00 Nonsubscribers $8.00
lating the characteristic velocity v ~ iss suggested. Method applies to bubbling regime in relatively inviscid liquids without surface effects.
Amine and Ammonium Silicates. 111. Ammonium Silicate Solutions. Describes the preparation of stable aqueous ammonium silicate
I . H . Lehrar, Monash University, Victoria, Australia MS.6 9 - 4 6 9 1 6 pages (1 table) I&EC Subscribers $4.00 Nonsubscribers $8.00
CHEMISTRY
