bluuebunny/crossref_metadata_2025 huggingface dataset:
Local Similarity Co‐ordinates for Parallel and Almost Parallel Turbulent Shear Flows
Authors: Hoffmeister M.
Published: May 2007

Taking into account dynamical effects local similarity numbers are developed. These involve both momentum and vorticity transfer transversal to the mean flow direction and can be regarded as a generalization of proposals made by L. Prandtl, G. I. Taylor, and Th. v. Kármán. The application to eight typical shear flows reveals common local properties and allows us to establish a common approximation for the eddy viscosity.
Zur elastisch‐plastischen Deformation der zentrisch erhitzten Scheibe
Authors: Gamer U.
Published: May 2007

Untersucht werden Spannungen, Verschiebung und plastische Dehnungen in einer zentrisch erhitzten idealplastischen Kreisscheibe unter Zugrundelegung der Fließbedingungen von Tresca und von v. Mises sowie der zugehörigen Fließregeln.
Application of the Method of One‐Dimensional Functionals to the Solution of Elasto‐Plastic Problems
Authors: Yanenko N. N. , Vasilkovsky S. N.
Published: May 2007

In the present paper a variational formulation of the method of the approximated factorization of multi‐dimensional differential operators is given. The method of one‐dimensional functionals being developed on the above mentioned basis allows to reduce the solution of multi‐dimensional problems in mathematical physics to the successive minimization of certain one‐dimensional functionals. The efficiency of the presented method of one‐dimensional functionals relative to well‐known variational methods is shown by solving two‐dimensional quasistatic boundary value problems with active loads when the plastic state is described by relations from the theory of Prandtl‐Reuß flows.
Influence of Noise on Duffing‐Van der Pol Oscillators
Authors: Ebeling W. , Herzel H. , Richert W. , Schimansky‐Geier L.
Published: May 2007

The stochastic motions of Duffing‐Van der Pol oscillators driven by white noise are investigated by using several theoretical methods: analytical and numerical calculations of the stationary probability distribution, analysis of the Hopf bifurcation, computer simulations and study of Lyapunov exponents. One observes a break of the radial symmetry and noise induced oscillations.
Non‐Linear Vibration of a Cantilever Beam of Variable Cross‐Section
Authors: Pielorz A. , Nadolski W.
Published: May 2007

Large amplitude free vibration of an inextensible thin elastic beam of a variable cross‐section is analysed. Although large deflections and rotations are considered the strains are small. It is shown how approximate solutions can be obtained by using Galerkin's method, and the effect of the variation of cross‐section is investigated. For the beam of constant cross‐section the results are compared with those of paper [3] and the exact solution of the special case of an ordinary differential equation obtained in the paper is considered. Additionally, a simple method for static deflections of the beam is proposed.
On the Convergence of the Fuzzy Clustering Algorithm “Fuzzy ISODATA”
Authors: Trzebiatowski G. , Bank B.
Published: May 2007

In der vorliegenden Arbeit wird für den unscharfen Partitionierungsalgorithmus “Fuzzy ISODATA” gezeigt, daß ausgehend von beliebigem Startpunkt jeder Häufungspunkt der generierten Folge ein stationärer Punkt des erweiterten, Quadratischen‐Fehlersummen‐Funktionals ist, welches als Partitionierungskriterium dient. Weiterhin liefert jeder dieser Häufungspunkte den gleichen Zielfunktionswert. Der Algorithmus “Fuzzy ISODATA” produziert keine Zyklen.
Ein superkonvergentes Zeitintegrationsverfahren für dynamische Systeme und andere Problemem‐ter Ordnung
Authors: Gärtner S.
Published: May 2007

Es wird eine allgemeine Methode zur direkten Integration von Anfangswertaufgaben m‐ter Ordnung erörtert. Die Approximation kann mit beliebigen Interpolationspolynomen (Lagrange, Hermite, Birkhoff usw.) erfolgen. Der Defektabgleich wird derart bestimmt, daß der Abbruchfehler eine höhere Ordnung erhält. Dieses Approximationsziel führt auf Bezichungen, mit denen sich die wichtigsten Verfahren zur direkten Zeitintegration dynamischer Systeme (Newmark, Wilson, Argyris, Malsch, Gellert usw.) herleiten und auf eine einheitliche Struktur zurückführen lassen. Außerdem wird gezeigt, daß Hermitesche Interpolationen mit einer korrespondierenden Kollokationsmethode auf diskrete Superkonvergenz höchster Ordnung führen.
Symmetrical Tensor Fields of Constant Eigenvalue Ratio and Solutions of the Stress Equations for Creeping Motion
Authors: Langbein W.
Published: May 2007

Methods of solution for the nonlinear stress tensor field equations of matter in the creeping motion state are analysed. For homogeneous matter in two space dimensions the problem proves to be equivalent to the construction of symmetrical tensor fields of constant eigenvalue ratio (1 − β)/(1 + β) and constant divergence g, where β and g are the internal friction parameter and the specific weight. A nonlinear second order differential equation remains if a modified Airy stress potential is introduced. This equation is solved generally for β2 1, g ≠ 0 and also for β2 = 1, g arbitrary. Physically, the corresponding stress fields describe weightless plastic matter and slowly moving anisotropic fluids respectively. For g ≠ 0 classes of new solutions are derived in the β2 = 1 case.
Further Results Concerning the Dynamic Response of Shear Deformable Elastic Orthotropic Plates
Authors: Librescu L. , Khdeir A. A. , Reddy J. N.
Published: May 2007

The dynamic response of orthotropic and transversely‐isotropic flat plates to dynamic transverse loading and in‐plane tensile loads constitutes the main topic of this paper. The dynamic loading conditions considered herein include sine, rectangular and triangular pulses while spatially, they are considered as sinusoidally distributed. The results obtained as per a higher‐order plate theory are compared with their first order transverse shear deformation and classical counterparts. In addition, some results concerning the associated free‐vibration and bi‐axial buckling of such plates are presented and comparisons with some of the available results are undertaken.
Darstellungen höherstufig‐tensorwertiger isotroper Funktionen
Authors: Silber G.
Published: May 2007

Es wird eine isotrope Potenzreihendarstellung für einen Tensor beliebiger (p‐ter) Stufe als Funktion einer Argumentenliste von Tensoren bis zur n‐ten Stufe entwickelt. Diese Darstellung läßt sich für den einfachsten Fall eines Tensors p‐ter Stufe als Funktion eines Vektors in einen geschlossenen Ausdruck kondensieren. Beide Entwicklungen ermöglichen einen Darstellungssatz transversal‐isotroper Stoffe, einschließlich aller Invarianten höherstufiger Tensorargumente. Wie zu erwarten, enthält diese Systematik beispielsweise auch die Materialgleichungen piezo‐elastischer Stoffe.
Thermal Stress Problem in a Fluid‐Filled Porous Circular Cylinder
Authors: Noda N.
Published: May 2007

The present paper deals with the one‐dimensional thermal stress problem in a fluid‐filled porous medium, when the fluid in a porous medium flows in a steady state. If a heat conduction equation taking into consideration the flow of the fluid in the porous medium is used, the governing equations for this thermal stress problem become simultaneous quasilinear differential equations. The closed formed solutions for thermal stresses may be obtained in a hollow circular cylinder of the porous medium. Numerical results for thermal stresses are shown in figures.
The Wigner Poisson Problem in a Crystal: Existence, Uniqueness, Semiclassical Limit in the One‐dimensional Case
Authors: Steinrück H.
Published: May 2007

We analyse a quantum‐mechanical model for the transport of electrons in a semiconductor. The model consists of the Wigner equation posed on the bounded Brillouin zone corresponding to the crystal lattice of the semiconductor, with a selfconsistent potential determined by a discrete Poisson equation. We prove global existence and uniqueness of solutions and consider the semiclassical limit.
An Asymptotically Fitted Finite Element Method for Convection Dominated Convection‐Diffusion‐Reaction Problems
Authors: Lube G.
Published: May 2007

This paper is concerned with the convergence of an asymptotically fitted variant of the finite method of streamline‐diffusion type for singularly perturbed elliptic boundary value problems modelling convection dominated convection‐diffusion problems. Numerical results are presented.
Instability by Extension of an Extensible Elastic Column
Authors: Atanacković T. M. , Djukić D. J. S. , Strauss A. M.
Published: May 2007

The instability of an elastic thin column, loaded by an extensional force is studied as a perturbed bifurcation problem. It is assumed that the column axis is extensible. The critical (buckling) load is determined from the single eigenvalue of the linearized equilibrium equations. The post‐critical shape of the column is determined using an extremum variational principle and Ritz procedure. The error estimate for the approximate solution is also presented.
On a Mathematical Comparison of the S‐ and T‐Criteria in Fracture Mechanics
Authors: Theocaris P. S. , Panagiotopoulos P. D.
Published: May 2007

We show that the S‐criterion of fracture mechanics is incompatible with the discontinuity of the velocity fields in the theory of ideal plasticity in contrast to the T‐criterion which permits a correct study of the fracture problem of an elastic ideally plastic body.
Runaway Phenomena and Fluid Approximation Under High Fields in Semiconductor Kinetic Theory
Authors: Poupaud F.
Published: May 2007

The problem of existence of homogeneous stationary solutions of the semiconductor Boltzmann equation is studied. We give a classification of the results according to the behaviour of the collision frequency for high velocities. We underline the case where a critical value of the electric field appears. When the collision frequency is bounded from below, these results allow to derive a fluid approximation of the kinetic equation. It is obtained as a limit of a perturbation which is convenient for high electric fields.
The Calculation of Wing‐Body Interference in Supersonic Flow by Means of SLLT
Authors: Jadic I.
Published: May 2007

The present paper is devoted to the aerodynamic analysis of wing‐fuselage configurations in supersonic flow by means of the lifting line theory (SLLT). This theory is based on the linearized small perturbations equation and assumes a constant distribution of circulation along the chord.

In order to simplify the present approach, the fuselage is assumed circular and infinite, while the wing is mid‐positioned. The comparisons cover the cases of rectangular and triangular planforms. The results presented herein show that the accuracy of the method is consistent with the linearized theory, enabling the estimation of wing‐body interference with a moderate computational effort.
On the Expansion of Plastic Regions in the Annular Parts of a Shrink Fit during Assemblage
Authors: Orçan Y. , Gamer U.
Published: May 2007

During assemblage of a shrink fit consisting of annular shaft and annular hub, partial or complete plastic deformation of either part can occur. If a perfectly plastic annulus is about to be fully plasticized, the interface pressure and the elastic‐plastic border radius of the other annulus, which may harden isotropically in an arbitrary way, assume stationary values. In addition to that, the case of two simultaneously fully plasticized annuli of perfectly plastic behavior is studied.
Absolute und konvektive Orr‐Sommerfeld‐Stabilitätsanalyse von Nachlaufprofilen eines Kraftfahrzeugs
Authors: Brevdo L. , Bohnsack E. , Oertel H.
Published: May 2007

Die experimentell gewonnenen, zeitlich gemittelten, turbulenten Nachlaufprofile hinter einem Kraftfahrzeug sind mit einer Orr‐Sommerfeld‐Analyse auf absolute und konvektive Instabilität hin untersucht worden. Dabei konnte ein absolute instabiler Bereich, der ungefähr deckungsgleich mit dem Bereich der quasistationären Rückströmung ist, identifiziert werden. Dies gibt Anlaß zu der Vermutung, daß eine Beeinflussung des Nachlaufs, z. B. durch Ausblasen, mit dem Ziel einer Verringerung des Widerstandes möglich ist. Die Vermutung wird in einem ersten Prinzipexperiment nachgewiesen.
Variational Formulations for Coupled BE/FE Methods in Elastostatics
Authors: Polizzotto C. , Zito M.
Published: May 2007

Ein gekoppeltes BEM/FEM‐Problem aus der Elastostatik, ein typisches Substrukturproblem, wird im Rahmen der symmetrisch‐definiten BEM behandelt. Es werden vier verschiedene Variationsformulierungen vorgestellt, in deren jeder die Transmissionsbedingungen gegenüber der Trennfläche zwischen FE‐Unterregion und BE‐Unterregion die Rolle natürlicher Randbedingungen spielen. Zwei der oben erwähnten Formulierungen sind Stationaritätsprinzipien in gemischter Form, die anderen beiden sind Sattelpunkt‐Prinzipien, d. h. Kombinationen des Rand‐min‐max‐Prinzips entweder mit dem Prinzip der minimalen Gesamtpotentialenergie oder mit dem Prinzip der minimalen Gesamtkomplementaritätsenergie. Jedes der oben angeführten gekoppelten Prinzipien kann für das durch unabhängige Modellierung für die Unbekannten auf der Trennfläche charakterisierte Diskretisierungsverfahren angewandt werden.
Calculating Some Details of Turbulent Motion in Plane Channel Flow
Authors: Schindler G.
Published: May 2007

Die Berechnung der Wirbelströmung in Grenzschichten kann man nach einem Vorschlag von W. Albring durch simultane Integration der Differentialgleichungen für das zeitgemittelte und das momentane Gleichgewicht stufenweise vornehmen. Die Methode läßt sich bei der turbulenten Reibungsschicht im ebenen Kanal anwenden. Das mittlere Geschwindigkeitsprofil und die Wirbelsysteme mit ihrer spektralen Verteilung werden berechnet. Durch Vergleich von Rechen‐ und Meßergebnissen erhält man in den wesentlichen Punkten eine Bestätigung der so gefundenen Lösung.
Investigation of a Non‐Thermal Equilibrium Flow of an Incompressible Fluid in a Cylindrical Tube Filled with Porous Media
Authors: Kuznetsov A. V.
Published: May 2007

In this paper, the transient response of a finite cylindrical tube filled with porous media to a non‐thermal equilibrium forced convective flow of an incompressible fluid through it is investigated. The analysis of the thermal charging of the packed bed is carried out. A two energy equation model is employed to simulate the temperature difference between the fluid and solid phase. Using the perturbation technique, an analytical solution for the problem is obtained. It is show that the temperature difference between the fluid and solid phases forms waves localized in space and propagating from the fluid inlet boundary in the direction of the flow. The amplitude of the waves decreases while the waves propagate downstream.
Regularisierung des Haftzustandes bei Coulombscher Reibung
Authors: Vielsack P.
Published: May 2007

Bei Stick‐slip‐Bewegungen infolge Coulombscher Reibung wird die volle Trennung von Gleit‐ und Haftbereichen in der Kontaktfläche berücksichtigt. Die zugehörigen Kontaktkräfte werden deshalb unstetig. Regularisierungsmethoden führen grenzschichtartige Näherungen für die Ruhezustände ein. Drei Näherungen werden mit der exakten Lösung eines mechanischen Systems verglichen.
Regularization Procedures of Singular Free Boundary Problems in Rotational Bingham Flows
Authors: Comparini E.
Published: May 2007

The flow of a Bingham fluid in a concentric cylinder viscometer can be give rise to free boundary problems. In the region between the two rotating cylinders the fluid behaves like a viscous fluid if the shear stress, expressed as a linear function of the shear rate, exceeds a yield value, and like a rigid body otherwise. The surfaces dividing fluid and rigid zones are the free boundaries, where we assume that the shear rate is zero. Starting from a model proposed in a previous work, where just one fluid and one rigid zone were present, here we study the physical problem taking into account the possible formation of further rigid zones inside the fluid. We introduce a kind of “regularization” of the problem, pointing out the existence of a unilateral constraint to which the formation of new rigid zones is related. Each time the constraint comes into play, the problem must be reformulated by letting new free boundaries appear bounding the newly created rigid region. Moreover we analyse the possible collapsing of the rigid zones.
Unsteady Flow of a Viscous Fluid Over a Plane Wall
Authors: Erdoǧan M. E.
Published: May 2007

The unsteady flow of an incompressible viscous fluid over a plane wall in the presence of a body force is considered. Three illustrative examples are given. In the first case, it is assumed that the body force is constant, in the second case the body force depends on time in the form of a positive power of time and in the third case the body force varies sinusoidally in time. In the case of the constant force the displacement and the momentum thickness grow as the square root of time as in the case of the flow due to a flat plate suddenly set in motion. It is shown that there are similarities between the flows considered in this paper and the Stoke's first and second problems.
The Compound Matrix Method for Multi‐Point Boundary‐Value Problems
Authors: Ivansson S.
Published: May 2007

The compound matrix method is generalized to handle multi‐point boundary‐value problems for first‐order ordinary differential‐equation (ODE) systems. A general treatment is given, covering all dimensions of the linear ODE system and different locations of the linear boundary conditions in a unified way. The back‐propagation step is performed in a new and simplified way. It is shown how local particular solutions can be used for reduction to a homogeneous ODE system. As an application case, efficient techniques are developed for wave‐propagation computations for range‐independent multi‐region fluid‐solid media. Thick homogeneous layers can be handled reliably without layer splitting.
The preparation and purification of monoglycerides
Authors: Choudhury R. Basu Roy
Published: May 2007

Mono‐ and diglycerides were produced by reacting the following oils with glycerol: coconut, peanut, sesame, linseed, and sardine. It was shown that the yield of monoglyceride was not dependent upon the fatty acid composition of the oil but on the solubility of glycerol in oil, which is dependent in part on the temperature. An excess of glycerol above that which is soluble does not change the composition of the reaction product. At 180°C, no more than 45% monoglycerides can be formed by glycerolysis.
A kinetic study of the autoxidation of methyl linoleate and linoleic acid emulsions in the presence of sodium chloride
Authors: Mabrouk Ahmed Fahmy , Dugan L. R.
Published: May 2007

Autoxidation of linoleic acid and methyl linoleate emulsions in aqueous buffer solutions was studied by the rate of oxygen uptake. The oxidation rates of methyl linoleate emulsions increased with an inerease in the pH of the buffer solution. With linoleic acid, oxidation rates rose until the increase reached its peak at pH 5.50 and then decreased gradually to a minimum at pH 8.00.

Oxidation rates of methyl linolente and linoleic acid emulsious decreased with increased concentration of NaCl in the system. The effect of variation of pH of the emulsion in the range investigated was similar to that in emulsions without NaCl. There was no evidence that NaCl accelerated the oxidation rates in the system.

The observed inhibitory effect of NaCl may result from the decreased solubility of oxygen in the emulsion with the increased concentration of NaCl. Consequently the availability of oxygen would be a limiting factor in oxidation rates.

The activation energy for the monomolecular and bimolecular reactions of methyl linoleate and linoleic acid autoxidation was found to be independent of the pH value and sodium chloride concentration of the system. The energy of activations for the monomolecular and bimolecular reactions of methyl linoleate and of linoleic acid are 22,000, 18,200, 19,600, and 16,400 cal./mol., respectively.

Spectrophotometric studies of the autoxidized emulsions of linoleic acid and its methyl ester indicate that the magnitude of the absorption at 2325 Å is the same at different pH values. On the contrary, the secondary products showing absorption at 2775 Å are to some extent dependent on the pH value of the emulsion.
Extraction of corn oil by three petroleum solvents
Authors: Arnold Lionel K. , Rowe William E.
Published: May 2007

Summary and conclusions

Rate‐extractions of corn germ oil by heptane, isoheptane, and hexane at the same temperature showed the latter two to be better solvents than heptane. Extraction rate increased with the temperature.

Countercurrent extraction in a continuous laboratory pilot plant showed hexane at 157°F. apparently equal to iso‐heptane at 192°F. It is suggested that the boiling of the hexane at 157°F. might account for the better extraction.

It can be concluded that hexane is at least as good a solvent for the extraction of corn oil from whole germ as is iso‐heptane.
Esters in human hair fat
Authors: Nicolaides N. , Foster Roscoe C.
Published: May 2007

A study was made of the hair fat composition of human adults with special reference to its ester content. Waxes, triglycerides, and a mixture of mono‐and di‐glycerides were isolated and charcterized. Indirect evidence is presented that the free acids of hair fat are derived from lipolysis of triglycerides. Some preferential esterification of some kinds of fatty acids as glycerides and others as waxes was observed. No significant differences could be observed in the analysis of the hair fat of adult males compared with that of adult females of the same age group.
Relation of amount and quality of protein in the diet to free gossypol tolerance by the rat
Authors: Cabell C. A. , Earle I. P.
Published: May 2007

Summary and Conclusions

The rat‐repletion method for protein assay has been used to estimate effects on tolerance for free gossypol of a) difference in source or kind of protein; b) level of total nitrogen or protein intake; and c) changes in amino acid content or balance in the nitrogen allowance. The data demonstrate that the first two of these factors at least influence the depression in weight repletion of these protein depleted rats which may be brought about by an intake of free gossypol. It has been shown that a daily intake of 9.5 mg. of free gossypol, when total daily protein intake is limited to 160 mg. of nitrogen, is a borderline level which depresses weight gain when the protein is supplied by some meal mixtures but is without effect with some others.

It has further been demonstrated that the toxic or weight‐depressing effect of 9.5 mg. of free gossypol which has been obtained with a nitrogen intake of 160 mg. may be nullified by increasing the protein intake 50% or more. Attempts to render ineffective an intake of 9.5 mg. gossypol at the lower nitrogen level by replacing a part of the nitrogen allowance with different amounts of some amino acid or amino acid combinations have not been markedly successful. The data do not identify the factor or factors in these protein supplements which influence gossypol toxicity. They do however point to the importance of considering both the amount and kind of dietary protein in attempts to establish a minimum level of free gossypol which is toxic for farm species, or a maximum level which will be tolerated.
Isomerization during hydrogenation. IV. Methyl eleostearate
Authors: Allen Robert R. , Kiess Arthur A.
Published: May 2007

The hydrogenation of methyl eleostearate with and without solvent has been studied. The data indicate the stepwise addition of two moles of hydrogen to the conjugated triene to produce equimolar amounts of 9‐, 10‐, 11‐, 12‐, and 13‐octadecenoates. Additional evidence for thecis‐9,trans‐11,trans‐13 structure of α‐eleostearic acid was obtained.
The isomerization of fats during hydrogenation and the metabolism of the component fatty acids
Authors: Allen Robert R. , Johnston Patricia V.
Published: May 2007

Extensive positional and geometrical isomerization occurs during the catalytic hydrogenation of edible oils and fats. The extent of this isomerization can be controlled by varying the conditions of hydrogenation.

Studies on the nutritional and metabolic aspects of the geometric isomers formed during the hydrogenation of edible fats indicate that the animal organism appears to be capable of metabolizingrans isomers. However there is some evidence to indicate that the deposition oftrans fatty acids in animal tissues may worsen a pre‐existing essential fatty acid deficiency.
Calculation of the distribution of the saturated and unsaturated acyl groups in fats, from pancreatic lipase hydrolysis data
Authors: Vander Wal R. J.
Published: May 2007

Evidence has been presented that the proportions of the glyceride types and isomeric forms in some fats in which C16−C18 chains are greatly in excess can be determined by calculations based on a) the percentage of saturated acyl groups in the whole fat, b) the percentage of saturated groups in the 2‐monoglycerides which can be derived from the fats by hydrolysis, c) the assumption that all the saturated and unsaturated acyl groups (S and U) present in each of the three positions in the molecules are dispersed therein at random, and d) the assumption that the proportions of S and U in the 1‐positions are identical with those in the 3‐positions. The method may apply to all predominantly C16−C18 fats and to other fats as well.
Preparation of pure fatty acid methyl esters by countercurrent distribution
Authors: Scholfield C. R. , Nowakowska Janina , Dutton H. J.
Published: May 2007

Acetonitrile‐pentane‐hexane makes a desirable solvent system for preparation of pure methyl esters because of its immiscibility, selectivity toward unsaturation, low boiling point, stability, and ease of recovery. Since separated esters are removed from the apparatus dissolved in the pentane‐hexane layer, successive batches may be fractionated without removing the acetonitrile layer from the instrument. Applications have been illustrated for the preparation of methyl linolenate from an 85% linolenate concentrate, methyl linoleate from safflower esters, and methyl arachidonate from pig liver lipids.

This procedure provides a source of “natural” fatty acids with the double bond configuration unchanged, in contrast to those from the conventional bromination‐debromination process. Automation of the process is completed by use of a recording refractometer which monitors concentration of solutions issuing from the extractor. Resolutions to be anticipated with lesser numbers of extraction tubes than 200 are calculated for an equal mixture of linoleate and linolenate.
Octadecylsulfuric acid. Properties of the acid, amine salts, and salts of amino acids
Authors: Maurer E. W. , Stirton A. J. , Weil J. K.
Published: May 2007

Octadecanol, hexadecanol, tetradecanol, and dodecanol were sulfated with chlorosulfonic acid, and the corresponding alkylsulfuric acids were isolated in a pure state as white crystalline solids with definite melting points.

Octadecylsulfuric acid resembles sodium octadecyl sulfate in detergent and surface‐active properties and in stability to hydrolysis at equal concentrations of hydrogen ion. It is more soluble in water than sodium octadecyl sulfate and readily soluble in organic solvents. The critical micelle concentration (0.0387 millimoles/I.) is only about one‐third that of the sodium salt.

Isolation of octadecylsulfuric acid as a useful chemical intermediate made possible the preparation of a number of salts with amines and amino acids and their rapid screening for useful properties.
Filtration‐extraction of flaxseed as affected by preparation variables
Authors: Knoepfler N. B. , Spadaro J. J. , McCourtney E. J. , Vix H. L. E.
Published: May 2007

The data presented show that the filtration‐extraction process can be applied to the extraction of oil from flaxseed. General conditions for preparing the material and for extraction have been established. Adequate comminution, cooking, and crisping yielded materials having necessary characteristics for the successful application of the filtration‐extraction process. Mass velocities in excess of 2,000 and residual lipides contents below 1% were obtained when these materials were slurried and extracted at slightly elevated temperatures (130°F.).

The conditions of rolling had an appreciable effect upon the efficiency of extraction of flaxseed. One pass through five‐high rolls with clearances of 0.002 in., 0.002 in., 0.002 in., and 0.000 in. between respective rolls proved satisfactory. Apparent optimum cooking moisture levels for efficient oil extraction fall between 17 and 24% maximum initial, and 8.0 to 10.5% as discharged from the cooker. Mass velocities were significantly lowered when maximum initial cooking moisture contents were below 14% since at these moisture levels it becomes necessary to reduce the moisture content to below 8%, as discharged from the cooker, to achieve suitable cooking. At these low moisture levels crisping by evaporative cooling is not effective.

The versatility of the filtration‐extraction process, which had been previously adapted to the extraction of oil from cottonseed, soybeans, sesame seed, peanuts, and rice bran, has been extended, with some minor but important modifications in the preparation and extraction conditions, to the extraction of oil from flaxseed.
Sulfates of ethoxylated tridecyl alcohol in dishwashing formulations
Authors: Schar W. C. , Paulson M. H. , Baumgartner F. N. , Wickson E. J.
Published: May 2007

The foam stability of several light‐duty liquid dishwashing formulations containing sulfated ethoxylates of tridecyl alcohol, lauryl alcohol, and nonylphenol have been compared. The effects of water hardness, sulfating agent, and ethylene oxide/hydrophobe mole ratio have been examined. In very soft water formulations containing alkanolamide and tridecyl alcohol derivatives were shown to be especially effective. At higher water‐hardnesses, combinations containing sulfated ethoxylates of tridecyl alcohol and nonylphenol performed best. Optimum ethylene oxide content for the sulfated tridecyl alcohol ethoxylates has been shown to be 4 to 5 moles/mole of alcohol regardless of water hardness or detergent concentration. The alcohol ethoxylates were shown to be more tolerant of stronger sulfating agents with respect to product quality than the alkylphenol ethoxylates.
Hydrogenation of methyl oleate in solvents
Authors: Cousins E. R. , Feuge R. O.
Published: May 2007

The hydrogenation of the oleic acid group was investigated with the objective of determining the effect of solvents on the reaction rate and the formation of positional and geometrical isomers. Methyl oleate, either alone or dissolved in one of several solvents, hexane, ethanol,n‐butyl ether, or acetic acid, was hydrogenated to an iodine value of about 50 under atmospheric pressure and at 30°C, with palladium‐on‐carbon and the W‐5 form of Raney nickel as catalysts.

Hydrogenation with palladium catalyst, with or without solvents, produced 76.6 to 79.1%trans bonds, based on the total double bonds. This is significantly greater than the 67% obtained previously. Hydrogenation products obtained with Raney nickel and solvents contained as little as 20.7%trans bonds at an iodine value of about 50. In two cases thetrans bonds were equal to about one‐third the positional isomers.

Positional isomers formed extensively when the Raney nickel was used in the absence of solvents and when the palladium catalyst was used. When the Raney nickel and solvents were used large proportions of double bonds were found in the original 9‐position.
Search for new industrial oils. IV
Authors: Earle F. R. , Glass C. A. , Geisinger Glenda C. , Wolff I. A. , Jones Quentin
Published: May 2007

Chemical screening of seed oils continues to reveal nature's diversity. This work provides leads to numerous species which warrant further research to investigate their oil and meal in greater detail, to appraise their crop potential, and to assess their practical value for providing new oilseeds.
Direct conversion of lipid components to their fatty acid methyl esters
Authors: Luddy Francis E. , Barford R. A. , Riemenschneider R. W.
Published: May 2007

Methyl esters were prepared from cholesteryl esters, phospholipids, and glycerides in substantially quantitative yields by methanolysis with large excess of sodium or potassium methoxide in absolute methanol.

A silicic acid chromatographic adsorption column technique was described, which was effective in separating methyl esters from unsaponifiables such as sterols, pigments, etc., and free acids.

Conditions for complete methanolysis of glyceride fats and oils requiring only 5 min. of reflux time were described.

Quantitative conversion of fatty acids to methyl esters was accomplished by direct esterification with absolute methanol containing 4% HCL or H2SO4 and by methylation with diazomethane.
Effect of autoxidation prior to deodorization on oxidative and flavor stability of soybean oil
Authors: Evans C. D. , Frankel E. N. , Cooney Patricia M. , Moser Helen A.
Published: May 2007

Oxidation prior to deodorization was shown to be detrimental to the flavor and oxidative stability of soybean oil. The increase in the nonvolatile carbonyl content of freshly deodorized oils was proportional to the peroxide value of the oils before deodorization. Rate of loss of flavor and oxidative stability of the oil were related to the extent of carbonyl development. All oils, whether or not they had been submitted to any known oxidation, contained some nonvolatile carbonyls. The loss in stability was not due to a loss of the antioxidant tocopherol.

Oxidized soybean oil methyl esters were shown to develop nonvolatile carbonyl compounds upon heating at deodorization temperatures. The addition of isolated methyl ester peroxide decomposition products to deodorized soybean oil reduced its flavor and oxidative stability in proportion to the amount added. The results obtained were parallel and similar to those obtained by oxidizing soybean oil prior to deodorization.

Flavor deterioration and undesirable flavors were typical of aging soybean oil whether or not the oils were oxidized before deodorization or whether an equivalent amount of nonvolatile thermal decomposition products was added to the oil. These oxidatively derived, nonvolatile carbonyl materials are believed to enter into the sequence of reactions that contribute to flavor instability and quality deterioration of soybean oil. The structure of these materials is not know.

This work indicates the importance of minimizing autoxidation in soybean oil particularly before deodorization to insure good oxidative and flavor stability.
Determination of water‐dispersible protein in soybean oil meals and flours
Authors: Paulsen Twila M. , Holt K. E. , Anderson R. E.
Published: May 2007

A method is presented for determination of Water‐Dispersible Protein, using a Hamilton Beach Drinkmaster #30 modified to accommodate Waring Blendor blades and cups. The probable sources of error in the method are discussed, and the precision of the method is shown, based on the results obtained in three laboratories using six different Modified Hamilton Beach Blendors.
The effect of mole ratio distribution on the physical properties of a polyoxyethylated alkylphenol
Authors: Mayhew R. L. , Hyatt R. C.
Published: May 2007

It has been shown repeatedly (1, 2, 3) that for polyoxyethylated nonionic surfactants a certain hydrophobe‐hydrophile balance (i.e., average mole ratio of ethylene oxide to hydrophobic material) is necessary to obtain maximum wetting, optimum detergency, etc. A study has been conducted to determine the effect of mole ratio distribution of ethylene oxide on the physical properties of a polyoxyethylated nonylphenol. This was accomplished by molecularly distilling two nonionics: a nonylphenol plus 6.0 moles of ethylene oxide and a nonylphenol plus 9.5 moles of ethylene oxide. The following conclusions have been reached concerning the effect of mole‐ratio distribution on the physical properties of these surfactants.

The mole ratio distribution of ethylene oxide in a polyoxyethylated nonylphenol follows the Poisson formula and curve in a manner analogous to the polyoxyethylene glycols (Fig. 1).

The hydrophobe‐hydrophile balance of the undistilled surfactant may be altered by molecular distillation. This is accomplished by narrowing the range of molecular species.

Wetting which is superior to the undistilled material may be effected by narrowing the distribution of molecular species (Figure 3).

Fractions from the distilled surfactant showed slight improvement in initial foam volume at certain mole ratios of ethylene oxide to base material over the undistilled material (Figure 6). No change in foam stability was noted.

Although there is an optimum ratio of ethylene oxide to the hydrophobic base at which maximum cotton or wool detergency is obtained, cotton and wool detergency are relatively unaffected by mole ratio distribution (Figure 7).

Surface and interfacial tension are also comparatively unaffected by mole ratio distribution change.

Emulsifying properties of these materials are adversely affected by narrowing the mole ratio distribution.
A further study of the tetrabromide method of estimating linoleic acid in fatty acid mixtures with pentane and heptane as solvents
Authors: White Mary F. , Brown J. B.
Published: May 2007

Known mixtures of linoleic and oleic acids were brominated in n‐pentane and n‐heptane and the yields of insoluble tetrabromides determined under precise conditions. In general, the yields were somewhat higher in both hydrocarbons than in Mallinckrodt petroleum ether. Tetrabromides were obtained in detectable amounts in mixtures containing as little as 10% linoleic acid when pentane is used. Therefore it is recommended that this solvent be employed in applying the procedure in the analysis of fatty acid mixtures. The linoleic acid contents of the fatty acids of several oils were estimated from the tetrabromidepentane curve and the results found to agree favorably with those obtained by thiocyanometry.
A laboratory apparatus for determining the rate of extraction of oil from oil‐bearing materials
Authors: Clark S. P. , Wamble A. Cecil
Published: May 2007

The equipment and the method have been described for measuring the rate of extraction of oil from oilbearing materials by solvent. The method consists essentially of immersing wire baskets containing the oil‐bearing material in a circulating stream of solvent for varying periods of time. After extraction, the baskets are centrifuged to remove excess solvent, and the residual oil in the solids is determined. The method is patterned after one devised by Boucheret al. (1) but has been modified and extended to other oil‐bearing materials.
Bleaching of wool grease
Authors: Anderson C. A. , Wood G. F.
Published: May 2007

Bleaching tests on three dark wool greases show that, among many systems tested, only hydrogen peroxide and sodium chlorite have significant effects. Pale greases are obtained by adding controlled amounts of sulphuric acid, phosphoric acid, or sodium phosphate with the hydrogen peroxide; sulphuric acid and phosphoric acid improve the bleaching power of sodium chlorite.
Effect of type of oil and site of administration on the fate of fatty acids in sheep
Authors: Erwin E. S. , Sterner W. , Marco G. J.
Published: May 2007

Safflower oil (S) and methyl myristate (M) were administered in the rumen (R) and abomasum (A) of sheep for 28 days. The digestibility of nitrogen and fiber were not affected by treatment. A larger proportion of fatty acids were digested with SA than with SR while the reverse was found with MR and MA. These differences were reflected in the fecal fatty acid composition. Regardless of treatment, the free fatty acid constituted approximately 75% of the fecal fat. MR and to a lesser extent SR increased the molar % of rumen propionate with a corresponding decrease in acetate. Fatty acid composition of rumen bacteria reflected the composition of the administrated oils. SR resulted in increased stearic and decreased linoleic acids in liver lipids while the adipose tissue remained constant. SA increased linoleic in both tissues. Markedly larger increases in myristic acid were found in adipose and liver lipids with MR compared to MA. Large increases in myristic acid in tissues were associated with decreased linoleic acid.
Nutritive value of marine oils. II. Effects ofin vivo antioxidants in feeding menhaden oil to swine
Authors: Oldfield J. E. , Sinnhuber R. O. , Rasheed A. A.
Published: May 2007

Five pair‐groups of swine were fed diets composed of crude feed materials to which 10% of clay‐bleached, light cold‐pressed menhaden oil was added. The oil was allowed to oxidize under controlled conditions and aliquots of fresh and oxidized oil were removed at peroxide values (PV) of 2.6, 15.5, and 61舒each of which was fed to one group of animals. Two additional animal groups received diets containing the highly oxidized oil (PV=61) plus either alpha‐tocopherol acetate or ethoxyquin. All oils were stored frozen and were mixed with the diets daily. Lard was fed at a similar 10% level to a control group of pigs. Both feed intakes and weight gains were progressively reduced as the diet oil was more highly oxidized. As oxidation of the oil increased, intensity of 舠yellow fat舡 increased and hemoglobin and hematocrit levels were progressively decreased. Both alpha‐tocopherol acetate and ethoxyquin actedin vivo to improve feed intake, rate of gain, and blood condition, and eliminated the incidence of steatitis.
Dietary antioxidants in young swine
Authors: Hill E. G.
Published: May 2007

Young swine obtained by hysterectomy were fed purified diets low in vitamin E and supplemented with d‐ॅ‐tocopheryl acetate and ethoxyquin (SantoquinR).

It was demonstrated that with very low levels of polyunsaturated fatty acids (PUFA) in the diet, both tocopherol and Santoquin protected the tissues of the pig from increased thiobarbituric acid (TBA) values and from increased hemolysis usually associated with low vitamin E status. When the dietary PUFA were increased to levels over 5%, the supplements of tocopherol and Santoquin protected against increased TBA values of tissue homogenates, but not against increased hemolysis of erythrocytes, even when blood serum showed substantial amounts of tocopherol.

Some of the interrelationships of dietary PUFA and ॅ‐tocopherol were demonstrated. It was shown that for each 1% of peroxidized corn oil added to the diet above 4%, roughly 100 mg of d‐ॅ‐tocopheryl acetate was necessary to protect the pigs from erythrocyte hemolysis.

The failure to reach a 舠zero舡 TBA value in vitamin E‐deficient swine tissue homogenates substantiated the theory ofin vivo lipid autoxidation, and the increased TBA values of incubated tissue homogenates demonstratedin vitro lipid autoxidation in tissues not protected by a biological antioxidant.
A note on the formation of 1,2‐diglycerides
Authors: Radlove S. B. , Madrigal R. V. , Slutkin R.
Published: May 2007

The reaction of glyceryl esters with fatty acids has been demonstrated to form an equilibrium mixture containing the 1,2‐isomer as well as the 1,3‐isomer previously reported (2). This procedure offers a method of synthesizing simple or mixed 1,2‐diglycerides. *** DIRECT SUPPORT *** A03O2167 00003
Some characteristics of the membranes protecting oil emulsions in protein solutions
Authors: Martínez Moreno Juan M. , Gómez Herrera C. , Márquez Delgado E. , Janer Del Valle C. , Duran Hidalgo L.
Published: May 2007

Expressed olive juice contains emulsified globules of olive oil. Electron photomicrographs of these globules show a rough membrane protecting them against coalescence. Some features of the membranes, such as the existence of “poles” and deposited microcrystals, are disclosed by the photographs and by electron diffraction patterns. Heavy metals appear to concentrate in the membranes and not in the aqueous medium.
The relationship between seed density and oil content in flax
Authors: Zimmerman Don C.
Published: May 2007

Density and oil content of seeds of 20 varieties of flax were found to be negatively correlated; r=−0.96. The density was determined by using the Beckman Model 930 Air Comparison Pycnometer. It is suggested that seed density can be used as a criterion for effective screening and selecting of flax lines with high oil content.
Evaluation of cottonseed meals prepared by extraction with acetone‐hexane‐water mixtures
Authors: Mann G. E. , Carter F. L. , Frampton V. L. , Watts A. B. , Johnson Charles
Published: May 2007

Eleven cottonseed meals have been prepared by batch extractions of a given lot of cottonseed with various acetone‐hexane‐water mixtures using several different extraction schedules. These meals, together with eight meals of commercial origin and a commercial soybean meal, have been subjected to chemical evaluation and assayed for protein quality using the growing chick as a test animal. In general the acetone‐hexane‐water meals were superior to the commercial cottonseed meals for promoting the growth of the chicks and, considering all the meals, a linear correlation was obtained between the logarithm of the weight gains and the available lysine contents of the meals. The free and total gossypol contents of the cottonseed meals appeared to have little or no influence on the growth rates.
Improved yields in the acid catalyzed addition of phenols and phenyl ethers to oleic acid
Authors: Ault W. C. , Eisner Abner
Published: May 2007

Phenols may be added to oleic acid in methanesulfonic acid solution to give the corresponding hydroxyphenylstearates in good yield. With phenol not only is the yield (ca 80%) better than that reported previously using other reagents but considerably less color is developed also. Surprisingly good yields (35–60%) were obtained with such complex phenols asp‐t‐butylcatechol and 2‐naphthol.
Reactions of unsaturated fatty alcohols. XIII. copolymers of unsaturated fatty vinyl ethers and cyclic monomers
Authors: Dufek E. J. , Gast L. E. , Teeter H. M.
Published: May 2007

Conjugated linseed, conjugated soybean, and nonconjugated linseed vinyl ethers were copolymerized with various cyclic comonomers. The comonomers used were dihydroabietyl, cyclohexyl, 5‐norbornene‐2‐methyl, di‐ and tetra‐hydrodicyclopentadienyl vinyl ethers, and cyclo‐and methylcyclo‐pentadiene.

All copolymers containing a cyclic comonomer gave baked films that are distinctly superior to unmodified drying oils or vinyl ether homopolymers in hardness and alkali resistance. Several of these copolymers air‐dried overnight to moderately hard, wrinkle‐free films.

The improvement in hardness and alkali resistance may be caused by the steric effects of the cyclic comonomers. These hold the fatty side chains apart thus increasing the proportion of intermolecular to intramolecular crosslinking.
The extraction and constitution of peat wax. Chromatographic fractionation of wax
Authors: Howard A. J. , Hamer D.
Published: May 2007

The extraction and properties of crude peat wax were investigated. The composition of this wax obtained with various solvents was assessed in terms of the components: resin, asphalt, and wax. It was concluded that extraction processes using benzene were likely to be of greatest value. Crude peat wax was further fractionated by chromatography to yield nine major fractions. These were distinguished by chromatographic behavior, fluorescence and spectral characteristics, and analytical composition. Preliminary work toward identification of individual components showed The presence of compounds of various types including hydrocarbons (e.g. perylene and many compounds containing one or more carboxyl, ester, carbonyl, or hydroxyl groups.