Showing papers by "Eindhoven University of Technology published in 1973"
TL;DR: In this article, the crystal structure of the TiAl3 layer has been found, depending on the temperature at which the layer was formed and on the composition of the starting alloy.
357 citations
TL;DR: The phase diagram of the Ti-Al system has been constructed using data from concentration-penetration curves recorded for various types of diffusion couples as discussed by the authors, and the phase diagram is found to agree with that proposed by Blackburn.
159 citations
TL;DR: The impact strength and modulus of polystyrene-graft copolymer blends could be made comparable to those of commercial rubber-modified impact polystyrenes by adjusting the fraction of copolymers in the blend as mentioned in this paper.
124 citations
TL;DR: In this article, the phonon spectra of GaSe, GaS, and their solid solutions are presented, and a detailed study of the phonons in the two GaSe $A$ doublets is presented.
Abstract: The $\stackrel{\ensuremath{\rightarrow}}{\mathrm{k}}\ensuremath{\approx}0$ phonon spectra of the layer crystals GaSe, GaS, and their solid solutions are presented. All phonon bands in GaSe (${D}_{3h}$ symmetry) and GaS (${D}_{6h}$ symmetry) are assigned and good agreement prevails between experimental results and group-theory predictions. It is shown that GaSe behaves approximately like a two-dimensional crystal; judging by the display of its phonons the interaction between layers given rise to Davydov doublets. It is demonstrated that these splittings in GaSe may be accurately measured. Owing to lack of inversion symmetry both components of some of the doublets are Raman active, and thus the splitting is yielded directly by a single Raman experiment. The largest splitting was found to be about 7 ${\mathrm{cm}}^{\ensuremath{-}1}$. A correspondence between GaSe doublets and GaS single Raman bands is proven. A detailed study of $\stackrel{\ensuremath{\rightarrow}}{\mathrm{k}}\ensuremath{\approx}0$ phonons in $\mathrm{Ga}{\mathrm{Se}}_{x}{\mathrm{S}}_{1\ensuremath{-}x}$ solid solutions is presented. It shows that these solid solutions yield an exceptional behavior of the phonon modes; some of the bands are of the one-mode type, while the other are of the two-mode type. In the two GaSe $A$ doublets, mode coupling between the two conjugate lines occurs, and both repulsion and intensity transfer are revealed and discussed.
82 citations
TL;DR: In this article, the authors reviewed the research work that examines the behavior of food aroma when water is removed by the various techniques used in food processing and discussed the economics of concentration and drying processes.
Abstract: Publisher Summary It is primarily food aroma that distinguishes the flavor of one food from that of another, and aroma quality often determines the acceptability of a food. When water is removed from a food, the loss or retention of the food aroma is one of the major considerations in the design of the food processing operation. This chapter reviews the research work that examines the behavior of food aroma when water is removed by the various techniques used in food processing. Water is removed from foods to provide microbiological stability, and to reduce storage and transportation costs. This chapter distinguishes between concentration and dehydration processes; the former includes those processes that increase solids content to about 60 % and the latter those that reduce water content to less than 10%. This chapter discusses the various aroma recovery processes. It then takes a look at the concentration processes where aromas are retained in the concentrate and drying processes where aroma is retained. This chapter ends with a discussion of the economics of concentration and drying processes.
77 citations
TL;DR: Open tubular columns made of soda glass may be successfully coated with polar stationary phases after etching with dry HCl, useful in difficult separations of steroids and their subsequent identification.
Abstract: Open tubular columns made of soda glass may be successfully coated with polar stationary phases after etching with dry HCl. Such columns are useful in difficult separations of steroids and their subsequent identification.
71 citations
TL;DR: In this paper, the ESR spectra of CoO-Al2O3, MoO3-Al 2O3 and CoMo2S4 were investigated in the oxidized state and after reduction with H2 + H2S (sometimes followed by a further treatment with H 2) or by H2.
61 citations
TL;DR: In this article, the stability range of the cubic spinel structure in the CuxMn3−xO4-system was determined with x-ray diffraction on quenched specimens.
56 citations
TL;DR: In this paper, the internal friction of sodium metaphosphate glasses containing from 0.016 to 0.330 wt% water has been investigated and a mechanism consisting of the cooperative motion of sodium ions and protons has been proposed for this peak.
Abstract: The internal friction of sodium metaphosphate glasses containing from 0.016 to 0.330 wt% water has been investigated. Weight loss and infrared absorption measurements were used to determine the water content. Of the two internal friction peaks observed between −100°C and ∼250°C, the second peak occurring above room temperature has a pronounced dependence upon the water content; increasing water content causing the activation energy to decrease as the peak increased in size. A mechanism consisting of the cooperative motion of sodium ions and protons has been proposed for this peak. It is concluded that the second peak in the NaPO 3 glasses and the similar peak in alkali silicate glasses is not associated with the movement of the non-bridging oxygen ions.
54 citations
01 Jan 1973
45 citations
TL;DR: In this paper, experiments on the oxidation of real sludges of different origins and compositions were carried out which lead to a mathematical model which described the results obtained, on basis of this model large scale reactors can be calculated.
Abstract: Experiments on the oxidation of real sludges of different origins and compositions were carried out which lead to a mathematical model which described the results obtained. On basis of this model large scale reactors can be calculated. The conversion of the Chicago installation is predicted to be 81% under conditions where the really obtained conversion is reported to be 80%.
18 Dec 1973
TL;DR: The theoretical rate equations derived from these results are in good agreement with experimental results as mentioned in this paper, and chain mechanisms are proposed for the reactions leading to these primary products, including n-propylbenzene, styrene, ethylene, 1-methylindan and o-propyltoluene.
Abstract: Kinetics of the primary cracking reactions occurring in the high pressure thermal hydrogenolysis of 1, 2, 3, 4-tetrahydronaphthalene (tetralin) and hydrindene (indan) were studied in a flow reactor at temperatures from 460° to 540°C, total pressures from 10 to 160 atm. and molar ratios of hydrogen-to-hydrocarbon from 2 to 100.
As primary cracking products from tetralin were identified n-butylbenzene, styrene, ethylene, 1-methylindan and o-propyltoluene.
From indan were obtained n-propylbenzene, toluene, ethylene, o-ethyl-toluene, o-xylene and methane.
Chain mechanisms are proposed for the reactions leading to these primary products.
The theoretical rate equations derived from these are in good agreement with experimental results.
TL;DR: An experimental check was made upon the theory given in Part I. In as discussed by the authors, Cracking catalyst was used as a solid and differently adsorbed tracer gases were used, and large traced gas bubbles were injected.
TL;DR: In this article, the anomalous thermal expansion of CuGaMnO 4 indicates that A-site Cu + ions from the stable ground state in presence of B-site Co 2+ and Mn 4+ ions is anomalous.
TL;DR: In this paper, the oxygen coverage on platinum anodes was determined at high anodic potentials in sulphuric acid solutions, and a limiting coverage was found for all concentrations, 1-11 M.
TL;DR: A survey of the recent work in the Department of Inorganic Chemistry of the Eindhoven University of Technology on the rheological properties of alkali borate glasses is given in this paper.
Abstract: A survey is given of the recent work in the Department of Inorganic Chemistry of the Eindhoven University of Technology on the rheological properties of alkali borate glasses.
TL;DR: In this article, the transport of GaS with the aid of iodine in a closed tube system to obtain the partial pressures, the main chemical reactions and the transport rates is discussed.
TL;DR: The equipment as described proved to be suitable and reliable for the analysis of chlorinated pesticides and with synthetic mixtures and with biological samples.
Abstract: The combination of the high resolving power of capillary columns and the extreme sensitivity of the electron capture detector gives us a powerful tool for the analysis of chlorinated pesticides. The connection of capillary columns to gas chromatographic equipment not speically designed for these, requires special adaptations. A generally suitable connection for capillary columns to injection ports and to the Hewlett Packard electron capture detector is described. The preparation of capillary columns suitable for pesticide analyses is discussed. Results obtained with synthetic mixtures and with biological samples are given. The equipment as described, proved to be suitable and reliable for the analysis of chlorinated pesticides.
TL;DR: Two simplified versions of this model are presented, one giving exactly the same results as the original model as long as nine key variables stay within their ''normal'' ranges, and an even simpler one giving nearly identical results.
TL;DR: In this paper, it was shown that in a model of a bipolar transistor with a rectangular configuration, the base-crowding effect may be represented by a diode and a resistor in parallel between the internal base point and the external base connection.
Abstract: It is shown that in a model of a bipolar transistor with a rectangular configuration, the base-crowding effect may be represented by a diode and a resistor in parallel between the internal base point and the external base connection with an accuracy of better than four percent.
TL;DR: The horizontal and vertical emittances of the extracted beam from the Eindhoven A.V.F. cyclotron have been measured for different particle energies and yields for the 45° bending magnets non-linear effects have been extracted from orbit integrations and comparison is made with the theoretical estimations of the second-order coefficients as discussed by the authors.
TL;DR: In this article, the authors extend these recipes to a general criterion for high vacuum sealing: a contact pressure at the rubber-metal interface of 13 kg/cm2, which is the minimum required compression force and the maximum allowed gap (if required) between mating flanges.
TL;DR: The zero field specific hear of NiBr 2 ·2H 2 O has been measured for 1.2 K T T 1c = 5.79 K and T 2c = 6.23 K as mentioned in this paper.
TL;DR: In this article, a revised table of values of some Argon II transitions is presented and a comment is given on the method of determining transitionprobability values in a previous paper of one of the authors.
Abstract: A comment is given on the method of determining transition-probability values in a previous paper of one of the authors. A revised table of values of some Argon II transitions is presented.
TL;DR: In this article, the ESR spectrum of the radical cation derived from p, p-bis-{phenyl(triphenylphosphorylidene)methyl}biphenyl reveals that spin density is found at both 31P nuclei.
Abstract: Analysis of the ESR spectrum of the radical cation, derived from p, p′-bis-{phenyl(triphenylphosphorylidene)methyl}biphenyl reveals that spin density is found at both 31P nuclei. Zero spin density is indicated for the outer phenyl rings. In the radical cation, derived from the corresponding m,m′-isomer the spin density is delocalized over one half of the molecule and interaction is found with only one phosphorus atom. In this system the spin density in the outside ring exceeds that in the biphenyl ring. The localization of the odd electron on one half of the molecule must be caused by a strong Jahn-Teller effect.
The assignment of the hyperfine coupling constants was based on spin density calculations according to the Unrestricted Hartree-Fock (UHF) method. From these calculations we also obtained an indication of the geometry of the radicals.
The synthesis of these compounds is reported.
TL;DR: In this article, a series of potassium barium borate glasses have been investigated as to their rheological properties and it has been found that all these glasses show deviations from "Newtonian" behaviour below temperatures corresponding to viscosities of 10 10 poises.
Abstract: Several series of potassium barium borate glasses have been investigated as to their rheological properties. It has been found, that all these glasses show deviations from ‘Newtonian’ behaviour below temperatures corresponding to viscosities of 10 10 poises. The activation energies of viscous flow are linear in both the potassium and barium mole percentages. For the ternary systems the pre-exponential factors of the viscosities do not decrease considerably with increasing metal ion content, contratry to what has been found in binary systems.
TL;DR: In this article, it was demonstrated that the Kirchhoff integration of reflector antennas leads to unreliable far sidelobes, if theoretical truncated feed patterns are used, and that the calculated radiation pattern does not yield 4π, but a greater value; the calculated noise temperature is therefore too high.
Abstract: It is demonstrated that calculation of the antenna patterns of reflector antennas, by means of Kirchhoff integration, leads to unreliable far sidelobes, if theoretical truncated feed patterns are used. The integrated radiation pattern does not yield 4π, but a greater value; the calculated noise temperature is therefore too high. Integration of calculated radiation patterns over 4π steradians is recommended to control the results.