bluuebunny/crossref_metadata_2025 huggingface dataset:
The consistency of plastic suspensions of the Bingham type
Authors: de Bruijn H. , Dols H. , Kuyper C.
Published: September 2010

)The consistency of a plastic suspension of the Bingham type was characterized by deriving φ‐τ diagrams from the D‐τ diagrams.

) In the case of the plastic suspensions of carbon in mineral oil it is deduced from the φ‐τ relation that the temperature coefficient of the consistency is determined almost entirely by the medium of suspension.

) Attention is called to the large errors caused by the turbulence occurring during measurements at high shearing stresses.

) In order to describe the curved part of a D‐τ diagram more exactly by means of constants, the concept of liquidation tendency is introduced. This liquidation tendency can be read off directly from a φ‐τ diagram.
Über einige Aminosäuren in Lolium perenne
Authors: de Man. Th. J.
Published: September 2010

In Lolium perenne wurden das freie Arginin, Tyrosin und Tryptophan bestimmt; es wurde gefunden, dass ein konstantes, vom Alter des Grases unabhängiges, Verhältnis zwischen diesen drei freien Aminosäuren besteht; durchschnittlich:

Auch zwischen dem im Eiweiss gebundenen Arginin, Tyrosin und Tryptophan besteht ein konstantes und gleiches Verhältnis.

Während der Nachprüfung einer von Roth für Pflanzen ausgearbeiteten Tryptophanbestimmung wurde gefunden, dass diese Methode für ligninhaltiges Material ungeeignet ist: im Material mit bekanntem Tryptophangehalt würde sogar eine einfache Ligninbestimmung, welche auf der nach Roth abgeänderten “Xanthoproteinreaktion” beruht, möglich sein.
Teneur en hydrates de carbone et „facteur d'albumine”︁ de la chair de moule
Authors: Gerritsen D. J. , van Pelt. J. G.
Published: September 2010

Les deux méthodes appliquées par Van de Velde pour la détermination des hydrates de carbone dans la chair de moule c. à d. 1) le chauffage à120°C avec de l'acide citrique à 5% et 2) la précipitation des hydrates de carbone d'une solution dans KOH conc. au moyen d'alcool éthylique, donnent, l'une et l'autre, des résultats beaucoup trop faibles.

Les valeurs que donne la méthode bien connue de Sachsse sont notablement plus élevées.

Par conséquent, la conclusion tirée par Van de Velde de ses analyses, que le “facteur d'albumine” est, pour la chair de moule, notablement plus élevé qu'on le pensait et s'élève à 8.0 environ, est erronée.
On the reaction of lithium picolyl with ethyl acetate
Authors: Beets M. G. J.
Published: September 2010

In connection with the article by Wibaut, Kloppenburg and Beets 1)

1)J. P. Wibaut, C. C. Kloppenburg and M. G. J. Beets, Rec. trav. chim. 63, 134 (1944).

, the reaction between lithium picolyl and ethyl acetate is described.
Some sulphanilamido‐nitro‐n‐propoxybenzenes
Authors: Verkade P. E. , Wepster B. M.
Published: September 2010

The preparation of some sulphanilamido‐nitro‐n‐propoxybenzenes is described. The stability of these substances toward aqueous alkalies and their resistance as well as that of their N4‐acetyl compounds toward deacylation by the method of Verkade and Witjens is discussed. The substances proved to be inactive against pneumococcal infections in mice.
Untersuchungen über Indolderivate. IV. Theoretische Betrachtungen über die drei Arten der Indolbildung aus α‐Arylaminoketonen
Authors: Verkade P. E. , Janetzky E. F.
Published: September 2010

Die vorliegende Abhandlung enthält einige theoretische Betrachtungen über die drei Arten der Indolbildung aus α‐Arylaminoketonen.
Induction, inhibition and the chain‐reaction theory, I
Authors: Jorissen W. P.
Published: September 2010

Not only the phenomena observed in the case of induced and retarded oxidation, but also those relating to the influence of the walls on the reactions in gases and to the extinction or retardation of explosive reactions, support the theory of chain reactions.
Hydrogenation of the fatty acids in butter with raney nickel
Authors: Kentie A. , Nauta W. Th.
Published: September 2010

A description is given of the complete hydrogenation of the fatty acids of butter to an iodine number of one in a very gentle way, namely with the help of a Raney‐nickel catalyst, at a low temperature and a pressure of one atmosphere. It proved to be possible to carry out the hydrogenation in aqueous solution. The best results were however obtained in alcoholic solution. The influence of temperature and a promotor (ammonium chloroplatinate) were studied.
Des Acridines Substituées. I. Sur quelques 9‐alcoyl‐ et 9‐aryl‐alcoyl‐acridines
Authors: Buu‐Hoï N. G. Ph. , Lecocq Jean
Published: September 2010

Dans le présent travail, les auteurs complètent les connaissances qu'on possède sur le groupe des méso‐alcoyl‐ et des méso‐arylalcoyl‐acridines, par la synthèse d'une série de ces composés et la description de leurs propriétés; le travail est complété par l'indication d'une méthode de préparation nouvelle de la 9‐benzoyl‐acridine, susceptible d'étre généralisée à la synthèse d'autres aryl‐9‐acridyl‐cétones.
Ueber Einige n‐Octylverbindungen
Authors: Rinkes I. J.
Published: September 2010

In nachtstehender Abhandlung werden die physikalischen Konstanten einiger n‐Octylverbindungen mitgeteilt, über die in der Literatur nach unserer Ansicht falsche Angaben vorkommen.
Inhibition, induction and the chain reaction theory, II: Inhibition by oxalate
Authors: Jorissen W. P. , van Calcar E. S.
Published: September 2010

Potassium and sodium oxalate retard the oxidation of ascorbic acid. Oxalate is thereby oxidized.
A new synthesis of methyl‐isopelletierine: Experiments on the synthesis of alkaloids of punica granatum 4th communication
Authors: Wibaut J. P. , Kloppenburg C. C.
Published: September 2010

By the action of dimethyl sulphate on 1‐(2‐pyridyl)‐propanone‐2 the corresponding quaternary N‐methylpyridinium salt is prepared; by partial hydrogenation of this compound we obtained 1‐(α‐N‐methylpiperidyl)‐propanone‐2 or methylisopelletierine in a yield of 47% of the theoretical calculated on α‐picolylmethylketone.
The Raman spectra of a number of polychloro compounds
Authors: Gerding H. , Rijnders G. W. A.
Published: September 2010

The Raman spectra are given of the following compounds, for the greater part prepared by Prins and put by him at our disposal: CCl3. CHCl2 (P), C3Cl8, CCl3.CHCl.CCl3 (P), CCl3.CCl2. CHCl2, CCl3. CHCl. CHCl2. CHCl2. CCl2. CHCl2. CHCl2. CHCl. CHCl2, CHCl2. CCl2. CHCl. CHCl2, CHCl2. CHCl. CHCl. CH2Cl (liquid and solid), CHCl2. CCl2. CCl2. CCl2. CCl2. CHCl2, CCl2 = CCl. CCl3, CCl2 = CCl. CHCl2, CHCl = CCl. CHCl2 (cis and trans), CCl2 = CCl. CCl2. CHCl. CCl3, CCl2 = CCl. CHCl. CCl2. CCl3, CCl2 = CCl. CCl2. CHCl. CHCl2, CHCl = CCl. CHCl. CHCl. CCl2. CHCl2, CCl2 = CCl. CCl = CCl. CCl3 (P), CCl2 = CCl. CCl2. CCl2. CCl = CCl2 (P) and CCl3. CCl = CCl. CCl = CCl. CCl3 (P).

Hydrogen vibrational frequencies (in particular valency frequencies) may be distinguished, which are characteristic for the groups —CHCl2, —CHCl— and CH2Cl— in saturated polychloro compounds (in which these groups are attached to chains of varying lengths with masses considerably exceeding that of chlorine). The valency frequency v(CH) in CHCl2— is about 40—50 cm−1 higher than that in ‐CHCl‐. It is probable that this difference must be ascribed to mutual interactions between hydrogen with chlorine of the same group and with chlorine atoms attached to neighbouring carbon atoms.

v(CH) for H attached to C = C in unsaturated compounds is considerably higher than v(CH) in saturated compounds. This increase must apparently be ascribed to a direct influence which the C = C double bond exerts on the C ‐ H bond (electron displacements). v(CH) vibrations in groups CHCl2‐ and ‐CHCl‐ retain in general about the values they possessed in the same groups in saturated compounds. Some general remarks are made regarding the influence of a continued substitution of H by Cl in methane on the sign and the magnitude of the charge present on the atoms of hydrogen.

Chain vibrational frequencies “v(C‐C)” in saturated, “v(CC)” and “v(C‐C)” in unsaturated compounds are discussed. The introduction of a double bond in a saturated polychloro compound results in an increase of the “v(C ‐ C)” chain vibrational frequencies also.

A comparison of “v(C ‐ Cl)” for Cl bound to C = C with “v(C ‐ Cl)” for Cl attached to C ‐ C in otherwise identical compounds containing only one atom of chlorine (or halogen), permits us to draw the conclusion that v(C ‐ Cl) is larger for Cl bound to C = C than for Cl at C ‐ C. The phenomenon of resonance in the unsaturated halogen compounds is at least partially responsible for this increase, as it causes the C‐Cl bond in the unsaturated compounds to possess a certain amount of double bond character.

In general we did not meet indications of the presence of rotational isomers caused by a restricted rotation around the C ‐ C single bond. Exception must be made for CHCl = CCl. CHCl2 (“cis”) and for the compounds C5Cl8 and C5Cl10, where such a hindered rotation plays a role in all probability.
The Preparation of 1‐Alkoxy‐2‐Amino‐4‐Nitrobenzenes in Aqueous Solution
Authors: Blanksma J. J.
Published: September 2010

1‐Alkoxy‐2‐amino‐4‐nitrobenzenes are prepared by reduction of 1‐alkoxy‐2:4‐dinitro‐benzenes with sodium disulphide in aqueous solution instead of in the appropriate alcohols with a corresponding economy in the use of the latter.

J. J. Blanksma and P. W. M. van der Weyden, This Journal 59, 629 (1940).

This can be accomplished without difficulty because the alkoxy group in the 1‐alkoxy‐2‐amino‐4‐nitrobenzenes is so slightly reactive that it is not replaced by hydroxyl during the reduction.
Über Die Synthese von Epi‐g‐glutathion: 10. Mitteilung über die Chemie der Tumoren
Authors: Kögl F. , Akkerman A. M.
Published: September 2010

In der Arbeit wird die Synthese eines stereoisomeren Glutathions beschrieben, das im Gegensatz zum gewöhnlichen Tripeptid den d‐Glutaminsäure‐Baustein enthält. Die Eigenschaften von Epi‐g‐glutathion (γ‐d‐Glutamyl‐1‐cysteinyl‐glycin) sind in Zusammenhang mit den Untersuchungen über die Konfiguration der Bausteine von Tumorproteinen von Interesse.
The adsorption of carbon disulphide vapour and water vapour by active charcoal
Authors: Vreedenberg H. A. , van Nouhuys H. L.
Published: September 2010

The adsorption isotherms of CS2 and of H2O by Norit charcoal were determined. In addition the adsorption from mixtures of the two vapours was investigated. Some measurements were carried out about the rate at which the equilibrium of adsorption is reached; in the case of adsorption from a mixture it was found that CS2 is at first adsorbed, but that afterwards H2O is substituted for the adsorbed CS2. All experimental results are described by means of a theory differing from the Langmuir theory by the assumption that the number of adsorbed molecules passing into the vapour phase per unit of time depends on the vapour pressure.
Synthèse de Nouveaux Acides Gras α, α‐Disubstitués
Authors: Buu‐Hoï N. G. Ph. , Cagniant Paul
Published: September 2010

Poursuivant leurs recherches sur la chimie des acides gras α, α‐disubstitués les auteurs décrivent dans le présent travail une série de représentants nouveaux de cette famille de substances. II est montré en outre que les amides des acides gras α, α‐diméthylés ne peuvent être saponifiés par la potasse alcoolique que lorsqu'ils renferment une double liaison dans leur molécule.
The purification of carbon rods for spectrochemical analysis: I. A simple apparatus for purification by means of resistance heating
Authors: Hoogland P. L.
Published: September 2010

A method is described for the purification of carbon electrodes for the purpose of obtaining material which can be used as supporting electrode in spectrochemical analysis of biological material according to the cathode‐layer method.

The principle of the method is that of raising the carbon rods to a very high temperature by resistance heating as employed by Gatterer.

Starting with “Siemens‐Plania Superbio Negativ Kohle” a useable product was obtained.

The heating process took place in such a way that several quantitative considerations could be related to it.
The purification of carbon rods for spectrochemical analysis: II. Carbon rods for spectrochemical analysis of solutions
Authors: Schmidt R.
Published: September 2010

The Scheibe‐Rivas method of spectrochemical analysis of solutions makes use of carbon rods which are impregnated with the solution to be analysed. The carbon rods must be pure, homogeneous and porous. The preparation of pure carbon rods fulfilling these requirements is described.
The sweet taste of 4‐nitro‐2‐aminotoluene, 4‐nitro‐2‐aminobenzoic acid and 2‐nitro‐4‐aminobenzoic acid
Authors: Blanksma J. J. , Hoegen D.
Published: September 2010

4‐Nitro‐2‐aminotoluene is 330 times as sweet as sugar. 2‐Nitro‐4‐aminotoluene is tasteless, 4‐nitro‐2‐aminobenzoic acid is 25 times, and 2‐nitro‐4‐aminobenzoic acid 120 times, as sweet as sugar. The acetyl derivatives of these compounds, as well as the esters of the acids and their acetyl derivatives, are all tasteless.
The bromination of 2‐aminopyridine in the gas phase at 500°
Authors: den Hertog H. J. , Bruin P.
Published: September 2010

When 2‐aminopyridine and bromine in the form of vapour diluted with nitrogen are passed over pumice at 500°, a violent reaction takes place, much carbon is deposited and a complex mixture of brominated aminopyridines is formed.

3 isomeric monobromo‐compounds could be isolated from the mixture, i.e. 2‐amino‐3‐bromopyridine, 2‐amino‐5‐bromopyridine and 2‐amino‐6‐bromopyridine. It contained further 3 dibromo‐compounds (2‐amino‐3,5‐dibromopyridine, 2‐amino‐3,6‐dibromo‐pyridine and 2‐amino‐5,6‐dibromopyridine) and one tribromo‐compound (2‐amino‐3,5,6‐tribromopyridine).

The reaction described differs considerably from the bromination of 2‐amino‐pyridine at room temperature, by the last process a mixture of only 2‐amino‐5‐bromo‐pyridine and 2‐amino‐3,5‐dibromopyridine being formed.
Vaccenic acid in butterfat and the fluctuations in its amount
Authors: Brouwer E. , Jonker‐Scheffener M. C. E.
Published: September 2010

Butterfat contains a notable quantity of vaccenic acid when the cows are on grass. On two winter rations the contents were only small. In butterfat from evening milk and from morning milk the contents are about the same.

There exists a positive correlation between the vaccenic acid content and the iodine value of butterfat. However, the iodine value being the same, the vaccenic acid contents on the winter rations were distinctly lower than on grass.
Quantitative evaluation of orientation in cellulose fibres from the X‐ray fibre diagram
Authors: Hermans J. J. , Hermans P. H. , Vermaas D. , Weidinger A.
Published: September 2010

The theory of fibre diagrams as given by Polanyi and first applied to cellulose fibres by Sisson and Kratky enables one to derive the orientation in a fibre from the intensity distribution in the diatropic interferences. Since these interferences are usually too weak in the X‐ray diagrams of cellulose fibres, we must resort to the paratropic reflexions. The present paper shows how these paratropic reflexions must be evaluated to obtain the orientation factor fr as a rational measure of average orientation. It is shown on experimental grounds that the proximity of the A4 interference does not invalidate the evaluation of the A3 sickle. A special procedure must be applied to fibres in which the orientation is not very pronounced, since here the interferences of the (021) planes partly overlap those of the paratropic A3 planes.

It is assumed throughout this article that in all experiments the Bragg angle is negligible. The correction required when dealing with finite Bragg angles is discussed in section 6.

The relation between orientation and optical constants is set forth in section 5. Finally, section 8 gives an illustration along with a short summary of the method.
Des Quinoléines Substituées. V: Polyalkyl‐Quinoléines et Polyalkyl‐Naphtoquinoléines
Authors: Buu‐Hoï Ng. Ph. , Guettier Daniel
Published: September 2010

On décrit la synthèse de plusieurs homologues polysubstituées de la quinoléine et des α‐ et β‐naphtoquinoléines, substances dont on désirait étudier certaines propriétés physiologiques. La méthode utilisée dans ces préparations est celle de Beyer‐Combes, méthode qui a également été appliquée à la synthèse de quelques amino‐quinoléines polysubstituées dont l'intensité de la fluorescence est tout à fait remarquable.
Equilibrium and stability
Authors: Bijvoet J. M. , Wiebenga E. H.
Published: September 2010

An isolated system in thermodynamical equilibrium is still in equilibrium after allowing for the possibility of interchange of heat or work between the system and properly adapted surroundings (i.e. for instance a bath at the temperature and pressure of the system). On the other hand the type of equilibrium ‐ stable, neutral or unstable ‐ can be changed by this contact.
Association in solutions of colloidal electrolytes; Hexanolamine elaidate and trihydroxy stearate
Authors: Gonick Emanuel , Mcbain James W.
Published: September 2010

Data for the electrical conductance and the lowering of freezing point of solutions of hexanolamine elaidate and of hexanolamine δ‐trihydroxy stearate are presented. It is shown that whereas the elaidate is a typical colloidal electrolyte, very highly associated into more or less conducting colloidal particles, the trihydroxy stearate, with soluble groups at both ends of the molecule, is an ordinary, fully dissociated electrolyte up to a concentration of at least 0.08 N.
On the diffusely diffracted radiation in the X‐ray diagrams of cellulose fibres
Authors: Hermans P. H. , Weidinger A.
Published: September 2010

This paper is concerned with the technique which can be used for the evaluation of the character of the X‐ray spectrum of the amorphous portion in cellulose from the general diffuse “background” scattering. It is shown that this spectrum consists of a very broad band with a flat maximum between the 101 and the 101 interference (fig. 3), corresponding to a spacing of 5‐6 Å.
Some observations on the reactions of bromoacetone and bromoacetaldehyde and their acetals with metals
Authors: Arens J. F. , van Dorp D. A.
Published: September 2010

It is impossible to prepare normal organometallic compounds from the acetals of bromoacetone or bromoacetaldehyde. Any reactions observed are due to the formation of enolethers.
A combined micro‐gravimetric and titrimetric micro‐determination of thallium in toxicological material
Authors: Reith J. F. , Gerritsma K. W.
Published: September 2010

A method is described for the specific determination of from 0.01 to 5 mg of thallium in excreta and organs. It is based upon the partial destructive oxidation with potassium chlorate and hydrochloric acid, extraction with ether as TlCl3, removal from the ether layer as TlCl with water containing SO2 and destruction of minute quantities of accompanying organic substances. The thallium is precipitated as TlI and isolated by centrifuging. The precipitate can be determined micro‐gravimetrically, however, with < 0.1 mg of thallium the error in weighing is relatively large.

The iodometric titration of the TlI here first described is always more accurate. The principles of sources of error of the operations are discussed. The ions Pb, Hg, Cu, As, Sb, Bi and Fe do not interfere.
A simple method for the fission of semicarbazones
Authors: Goldschmidt  , Veer W. L. C.
Published: September 2010

This paper describes a simple method for the fission of semicarbazones with sodium nitrite in glacial acetic acid solution.
The Wurtz‐Fittig reaction II
Authors: Sirks J. F.
Published: September 2010

The action of sodium on a mixture of 1,3‐dibromopropane and a para‐substituted bromobenzene was investigated.
The difference in reactivity of aromatic bonds
Authors: Kooyman E. C. , Ketelaar J. A. A.
Published: September 2010

A hypothesis

) Compare E. C. Kooyman, Thesis, Amsterdam 1946, § 3.

) is given concerning the mechanism of some reactions of aromatic compounds, which tries to reconcile the fact that, as a result of resonance, no double bonds are present in these molecules, and the conclusion following from organic chemical experiments, that in some aromatic molecules fixed double bonds seem to occur.

The hypothesis offers among other things an explanation for the striking difference between the 1,2‐ and 2,3–bonds in naphthalene.
Studies of gas absorption: II. Application of the liquid film resistance relationship to the absorption of carbon dioxide by solutions of diethanolamine
Authors: van Krevelen D. W. , Hoftijzer P. J.
Published: September 2010

The general equation for liquid film resistance to gas absorption in scrubbers, derived by us in a previous paper 1), was applied to experiments of Cryder and Maloney2), treating the absorption of carbon dioxide in diethanolamine solutions. Our equation proved to be valid also in this case, when it is assumed that the reaction is a pseudo‐third order reaction. In reality it will be a succession of two second order reactions, as no temperature influence on the reaction velocity constant is found.
Chemical constituents of mundulea suberosa benth. Part I
Authors: Meijer Th. M.
Published: September 2010

A review is given of the literature on the occurrence and application of Mundulea suberosa. Chemical investigation of the bark of the branches led to the isolation of rotenone, a white substance C23H20O7, m.p. 193‐195° C, and from the root bark a yellow substance C23H20O7, m.p. 216‐220° C was isolated. Both products contained two methoxyl groups. Treatment of the colourless crystals with glacial acetic acid and sulphuric acid furnished a yellow product of the composition C23H18O6. Oxidation with chromic acid gave a substance C23H18O7, m.p. 262°C. A comparison was made with known rotenoid substance of similar composition.
Preparation of hydrogen peroxide from the peroxides formed on oxidizing propane
Authors: Kooijman P. L.
Published: September 2010

An investigation is described of the conversion of the peroxide solution, obtained on oxidizing propane, into hydrogen peroxide. The method of doing this is based on the conversion of the said peroxide solution into calcium or barium peroxide by means of calcium or barium hydroxide, which process gives a high yield. Following this conversion, the calcium or barium peroxide is transferred into a dilute hydrogen peroxide solution by means of carbon dioxide, whereas the carbonate is precipitated and filtered off. This conversion, too, proceeds with a high yield.
The colorimetric evaluation of Derris root
Authors: Meijer Th. M. , Rachmad A.
Published: September 2010

A more precise procedure for the colorimetric evaluation of Derris root is described, making use of the colour which rotenone and the matter which may be extracted from Derris root by ether produce with concentrated sulphuric acid containing a trace of sodium nitrite. Rotenone is used as a standard. A number of samples of Derris powder with varying contents of rotenone and ether extract were analyzed. It was found that the amount of “rotenoid” substances present in the different samples corresponded fairly well to the ether extract.
Preparation and some physical constants of 2‐methyltetradecane and 3‐methylpentadecane
Authors: Lunshof H. J. , van Steenis J. , Waterman H. I.
Published: September 2010

Since the authors were interested in the physical constants of some branched chain hydrocarbons in connection with other work, 2‐methyltetradecane and 3‐methylpentadecane were prepared and some of their physical constants determined.
On metastable eutectics in binary salt systems
Authors: Korvezee A. E. , Dingemans P. , Dijkgraaf L. L.
Published: September 2010

The eutectic in any given binary system cannot be derived from the melting point and heat of fusion of the components. Formulae based upon an ideal form of the melting‐point curves cannot of course give more than a rough approximation.

When one of the components in a binary system occurs in two crystalline modifications, a metastable eutectic occurs in addition to the stable eutectic. If the transition point lies close to this metastable eutectic, simple formulae, based upon ideal behaviour, can be derived for the distance between the two eutectics.

With the small differences in question these formulae are found to be useful for salt melts. The values found give reasonable agreement with those which are obtained by extrapolation of relative vapour‐pressure curves.
On the structure of leucaenine: 4th communication
Authors: Kleipool R. J. C. , Wibaut J. P.
Published: September 2010

The synthesis of two N‐substituted derivatives of 3‐hydroxypyridone‐4 is described.
Optical rotation and atomic dimension
Authors: Gerrard W. , Lessing W.
Published: September 2010

Relevant remarks on the recent article by Brauns are made. In his essential observations he was preceded by Gerrard, but this precedence was not acknowledged.
The preparation of peroxides by the oxidation of ethane
Authors: Kooijman P. L.
Published: September 2010

A description is given of an investigation into the optimum conditions for preparation of the peroxides which are formed when ethane is incompletely oxidized with oxygen. It has appeared that under optimum reaction conditions the ethane is only reactive in a high temperature range. On adding a small quantity of acetaldehyde, however, it also reacts at low temperature producing peroxides. The addition of 0.1% by vol. of acetaldehyde vapour to the ethane‐oxygen mixture proved to be a means of raising the hydrogen‐peroxide yield from 0.4 mol. % to 0.7 mol. % of the ethane feed.
Vapour‐liquid equilibria in ternary systems. V. The system water‐formic acid‐metaxylene
Authors: Reinders W. , de Minjer C. H.
Published: September 2010

The equilibria between liquid and vapour in the system water‐formic acid‐metaxylene have been investigated. The system has a saddle point in the region of partial miscibility, which is situated for a pressure of 760 mm at a temperature of 97.5° and at a vapour composition of 10.6% water, 40.4% formic acid and 49.0% m‐xylene.

From these equilibria was deduced how one can use m‐xylene for dehydrating the azeotropic water‐formic acid mixture with 22.6% water and with what yield.
Gradual separation and economy: 5th Communication, separation by distillation
Authors: Treub J. P.
Published: September 2010

In this communication the requirements a distillation column has to meet will be dealt with and the way, wherein a theoretically correct column may be built up and has to be economically manipulated, will be shown. In such a column, which has an “uphold”, that is negligible, relations may be applied for practical purposes, which hold for theoretical plates, so that in many cases a simple mathematical analysis of the process of distillation is possible.
Quantity of adsorbent and temperature as factors in adsorption from solution
Authors: Groves T. E. , Bowden S. T. , Jones W. J.
Published: September 2010

The effect of variation of mass of adsorbent and of temperature on the adsorption of acetic acid from dilute aqueous solution by charcoal has been measured. It has been found, first, in agreement with Burgers but contrary to Wo. Ostwald, that for each temperature the amount of solute adsorbed per unit mass of adsorbent is a uniform function of the final concentration of the solution, independent of the quantity of adsorbent used per unit volume of the solution, and secondly, in disagreement with some of the results published by Freundlich, that for a given value of the final concentration the amount adsorbed per unit mass of adsorbent falls consistently as the temperature is raised.
A cis‐C18‐ketone, related to vitamin A
Authors: Arens J. F. , van Dorp D. A.
Published: September 2010

A by‐product of the Reformatzky‐reaction of β‐ionone and ethyl γ‐bromocrotonate is a cis‐β‐ionylidene‐crotonic acid I. This acid can easily be converted into the cis‐C18‐ketone by means of lithiummethyl.
Über 4(7)‐amino‐benzimidazol: 2. Mitteilung über des‐aza‐purin‐derivate
Authors: van der Want G. M.
Published: September 2010

In der vorliegenden Arbeit wird gezeigt, dass die in der Literatur als 4(7)‐Amino‐benzimidazol beschriebene Verbindung in Wirklichkeit die Aminogruppe an Stelle 5 (bzw. 6) trägt. Das bisher unbekannte 4(7)‐Aminobenzimidazol ‐ dem wegen seiner strukturellen Beziehung zu Adenin ein gewisses Interesse zukommt ‐ wurde dargestellt und mit der isomeren Verbindung verglichen.
The calcium salts obtained by the complete extraction of coca leaves and the determination of the acid esters of l‐nor‐ecgonine
Authors: de Jong A. W. K.
Published: September 2010

The calcium salts contain besides the acid esters of l‐nor‐ecgonine, calcium salts of ordinary acids, one or more esters of ordinary acids and an amide.

The quantity of the acid ester of l‐nor‐ecgonine is determined in the following way. The calcium salts are acidified with a few drops of strong HCl solution and the acids and the esters of ordinary acids extracted by ether. The neutralized HCl solution basified with a known quantity of n/10 NaOH solution and boiled in a Kjehldal apparatus as used for ammonia determinations. The quantity of acid esters is equivalent to the loss of NaOH diminished by the quantity of ammonia obtained.
The vapour pressure of saturated solutions of sodium nitrate in water
Authors: Dingemans P. , Dijkgraaf L. L.
Published: September 2010

The vapour pressure of saturated solutions of NaNO3 in water was measured from 10° C to 150° C.

From these measurements it is found that the relative vapour pressure p/pw plotted as a function of the temperature gives a slightly curved line, as previously obtained for some other saturated salt solutions

Miss A. E. Korvezee and P. Dingemans, Rec. trav. chim. 62, 625 (1943).

).
Investigations on sterols II): Vitamin‐D2 and ‐D3 in irradiated sterol from the mussel (mytilus edulis))
Authors: van der Vliet J.
Published: September 2010

The following compounds have been detected in the sterol fraction from the mussel (mytilus edulis) after irradiation with ultra‐violet light: Vitamin‐D2 and ‐D3 and a compound closely related to ‐D2 and having a vitamin‐D structure, but which is practically devoid of anti‐rachitic action. A mixture of this compound with vitamin‐D2 has been isolated in a crystalline state (‐Dx).
Decomposition of o‐hydroxydiazonium compounds by light
Authors: de Jonge J. , Dijkstra R.
Published: September 2010

Conditions could be found for decomposing a solution of an o‐hydroxybenzene diazonium compound into a colourless product.

Such an irradiation product couples with diazonium salts in slightly acidic solution to red‐shaded dyes according to a bimolecular reaction.

However, it is not stable in solution at room temperature, but is converted slowly into a non‐coupling dimeric form.

The irradiation of the diazonium salt gives rise to a new, weak acid function, that disappears again on heating, with evolution of CO2.

Titration curves show that the o‐hydroxybenzene‐ and o‐hydroxynaphthalene‐diazonium compounds are decomposed in a similar way.

Two irradiation products of o‐hydroxynaphthalene‐diazonium compounds have been isolated.

Our results are completely understood by assuming the conversion of the benzene‐nucleus into a five‐membered ring, as recently concluded by Süs from other experiments.
The chemistry of 2‐aminofluorene: 2. Reaction with dihydroxymalonic ester
Authors: Neish W. J. P.
Published: September 2010

2‐Aminofluorene reacts with dihydroxymalonic ester yielding ethyl fluorene dioxindole carboxylate, which is readily hydrolysed and oxidised to an isatin derivative, 2′,3′‐indeno‐4,5‐isatin. The latter compound yields an oxime.
Titration of adsorbed acids
Authors: Tendeloo H. J. C. , Mans A. E. , de Hoogh G.
Published: September 2010

The researches here described deal with electrometric titrations of strong acids in the presence of adsorption charcoal (Norit). The titration curves of the system containing charcoal are of the type of titration curves of weak acids; the systems have a pronounced buffer capacity.
Steric effects on mesomerism: I. General considerations on the deacylation of aromatic acylaminocompounds with a nitro group in the ortho‐ or para‐position
Authors: Wepster B. M. , Verkade P. E.
Published: September 2010

This paper is the first of a series dealing with an investigation of the rates of deacylation of aromatic acylamino compounds having a nitro group in ortho‐ or para‐position, with the aim of obtaining further (semi‐) quantitative information with regard to “steric effects on mesomerism” (“steric hindrance of resonance”).

In the first section some remarks on the nomenclature have been made, more in particular on the use of the “neutral” word “effect”, rather than the more customary “hindrance”. Further, it has been pointed out that the so‐called “Mills‐Nixon effect” should be regarded as a special case of steric effects on mesomerism, viz. as a steric effect on mesomerism due to changes in valency angles.

The mechanism of the deacylation has been discussed in some detail; the mesomerism in the ortho‐ or para‐nitrophenylamino grouping is regarded to be mainly responsible for the “catalytic” deacylation.

The question as to whether the slow deacylation observed in some cases might be caused by steric hindrance in the classical sense, rather than by steric effects on mesomerism, has been considered, the conclusion being that steric hindrance is certainly not of prime importance.

In the last section the method by which the rates of deacylation are compared in order to get an insight into the magnitudes of the steric effects on the mesomerism, has been given and discussed briefly.
Diphenyl derivatives I. Basic 2‐diphenyl compounds related to the morphine molecule
Authors: Goldschmidt S. T. , Veer W. L. C.
Published: September 2010

The morphine molecule may be considered as derived from 2‐phenylbenzylamine or α‐(2‐diphenyl)‐β‐aminoethane, partially or totally hydrogenated. The synthesis of such compounds and their conversion into N‐substituted alkyl‐ or dialkyl‐aminoalkyl derivatives is described. Hydrogenation of 2‐phenylbenzyl cyanide afforded α‐(2‐diphenyl)‐β‐aminoethane. The synthesis of 2‐aryl‐hexahydrobenzylamines, 2‐cyclohexyl‐benzylamine and 2‐cyclohexylhexahydrobenzylamine is also described. A number of N‐substituted derivatives of these compounds has been prepared.

A summary of the pharmacological properties of the substances described is given.
The Disintegration of Fire Bricks by Carbon Monoxide: Part I. The determination of the disintegrability of fire bricks general considerations
Authors: Bohlken S. F.
Published: September 2010

A new method for the determination of the disintegrability of fire bricks by carbon monoxide is described. The method is characterised by careful crushing of the brick and by leading a synthetic gas mixture of about 3% hydrogen, 34.5% carbon monoxide and 62.5% nitrogen and argon over 100 g of this grog at 600° or 800° C at a rate of 5‐liter/h, and titrating the developed carbon dioxide after absorption in baryta water.

Several precautions, the preparation of the gas mixture, the results in field tests, and a tentative specification for the resistance to disintegration are given.
Kinetics of gas‐liquid reactions. Part II: Application of general theory to experimental data
Authors: van Krevelen D. W. , van Hooren C. J.
Published: September 2010

The results of the theoretical considerations described in Part I are applied to experiments on chemical absorption of carbon dioxide in alkali hydroxide solutions and in ammoniacal solutions.

The calculated values for the rate of absorption prove to be in good agreement with the experimental data.
Calculations of force constants for the molecules P4O6, P4O10 and P4O6S4 with the help of raman effect data
Authors: van Brederode H. , Gerding H.
Published: September 2010

Numerical equations are derived for the frequencies of the total symmetrical vibrations of the molecules of P4O6, P4O6S4 and P4O6O4, all of which have the symmetry Td, thereby making use of the bond distances and bond angles determined by Hampson and Stosick and by Stosick in their electron diffraction measurements. Force constants have been calculated for P4O4, using the results of Raman spectroscopic investigations, which we made previously, and the simplified assumption that the two deformational force constants d1 and d2 have the same value. f1 is then found to be 4.75 × 105 and d1 = d2 to be 0.35 × 105 dyne/cm. This value for f substituted in Badger's formula, leads to a value for the P—O bond distance, which is in good agreement with that determined directly by the electron diffraction method.

For P4O6S4 and P4O6O4 that value for f2 (the force constant for the P = S or P = O bond) is determined, which leads to the best agreement between calculated frequencies of the symmetrical vibrations and those experimentally found in the Raman effect assuming that d1 = d2 and that f1/d1 = f2/d3 = 13.6 as in P4O6. For P4O6S4, f2 = 5.5 × 105 dyne/cm is found. This value introduced into Badger's formula gives rp=s = 1.85 Å, in excellent agreement with the experimental value.

For P4O6O4, f2 = 11.0 × 105. Å certain discrepancy does exist here between rP=O calculated (1.46 Å) and the bond length found (1.39 Å).

Finally, the modes of motion of the atoms in the symmetrical vibrations of P4O6O4 were calculated and graphically represented. There is good agreement between the vibrational motions found and those assumed previously.
Some experiments with the Baird associates infra‐red gas analyser
Authors: Deinum H. W. , Rietveld B. J.
Published: September 2010

The determination of carbon dioxide, methane, carbon monoxide, water vapour, benzene vapour and toluene vapour by means of the Baird Infra‐Red Gas Analyser was investigated. The selectivity of the determination of methane in presence of carbon dioxide and carbon monoxide and of carbon dioxide in presence of methane and carbon monoxide was checked. An extensive investigation of the stability of the recordings brought to light that fluctuations in the frequency of the electricity supply render the recordings useless. This drawback was surmounted by feeding the infra‐red source independent of the electricity supply.
The crystal structure of gammexane
Authors: Bijvoet J. M.
Published: September 2010

X‐ray analysis of the crystals of gammexane, 1,2,3,4,5,6‐hexachloro‐cyclohexane, proves this isomer to be of the p,p,p,e,e,e type.
Determination of the degree of saturation with oxygen of blood by means of the leifo photometer
Authors: Pieters H. A. J. , Hanssen W. J.
Published: September 2010

Spectrophotometric determinations of the percentage of oxyhaemoglobin in blood are described in the literature.

In applying this method we encountered some difficulties especially in relation to sampling. In this communication we intend to give a summary of our experience with this method.

The following factors were examined:

the most favourable wave lengths for measuring the maximal cq minimal absorption of oxyhaemoglobin and haemoglobin,

the influence of saponin (used for haemolysation) on the extinctions,

reproducibility of the quotients of the extinctions (E1 and E2) measured at two different wave lengths (λ1 and λ2) of haemoglobin and of oxyhaemoglobin, in blood taken from different persons,

sampling and treatment of the sample so that contact with air is avoided.

From the results we calculated the oxyhaemoglobin content of blood partly saturated with oxygen (0‐100% of oxyhaemoglobin) as a function of the quotient of the extinctions measured at two wave lengths.

The influence of CO‐haemoglobin was investigated.

A procedure is described.
Les Propriétés du Groupe Sulfonyle: II. L'isomérisation de l'allylbenzylsulfone en propénylbenzylsulfone
Authors: Backer H. J. , de Jong G. J.
Published: September 2010

L'isomérisation des sulfones cycliques des butadiènes consiste en un déplacement de la double liaison de la position β à la position α par rapport au groupe sulfonyle. Le fait qu'on n'a pas pu réaliser cette réaction chez une sulfone non saturée acyclique (allylbenzylsulfone) doit être attribué à des conditions qui provoquent une addition du solvant. A l'aide d'amines tertiaires, les auteurs ont réussi cette isomérisation.

L'addition d'alcool, de phénol, en présence de leur dérivé sodique, et d'amines donne, dans chaque cas, un seul produit substitue en position β. Ces additions s'accomplissent probablement par l'intermédiaire de la sulfone isomère (propénylbenzylsulfone), qui prend naissance en milieu nucléophile.

L'addition de l'acide iodhydrique à l'allylbenzylsulfone donne deux isomères, les iodures β et γ. Lorsqu'on chauffe le mélange avec de l'ammoniac alcoolique, le β‐iodure perd de l'acide iodhydrique en engendrant la propénylbenzylsulfone; le γ‐iodure n'est pas décomposé.
Amides II. Acylation of amides to diacylimines
Authors: Polya J. B. , Spotswood T. M.
Published: September 2010

Three acylating mechanisms are involved in the reaction between amides and anhydrides. In the aliphatic series all mechanisms are governed by the inductive effects operating in the reactants.

Amides act as acids towards anhydrides.

Diacylimines and the corresponding anhydrides acylate alcohols by the same mechanism.

A new compound, propionylchloroacetamide, has been prepared. Properties of some diacylimines have been established. Uses for diacylimines are suggested.
The system methylmethacrylate ‐ methanol ‐ water
Authors: Kooi J.
Published: September 2010

The curves of partial miscibility of the system methylmethacrylate‐methanol‐water have been determined at 0°, 25° and 50° C, as well as the variation of the density at 25° along the curve of partial miscibility. A graph has been constructed on this basis, which gives the composition of the two coexisting phases of the system from the density of one of the phases. The critical solubility point at 25° C is situated at 32.45% methanol. 38.50% methylmethacrylate and 29.05% water.
Alkalimetric titration of phosphoric acid and phosphates
Authors: Dijksman J. C. W.
Published: September 2010

Many contradictory data are known concerning the alkalimetric titration of phosphoric acid. The uncertainties, which have received a solution in this investigation, concern:

the correct titration exponent in titration to mono or diphosphate;

the correct composition of crystalline disodium phosphate which turned out to be exactly Na2HPO4. 12H2O;

the inflexion points in the titration curve were found to coincide with the equivalence points.

Further a search was made for a suitable and accurate method of carrying out an alkalimetric phosphate determination in phosphates containing calcium, aluminium and iron, because the known methods are all unreliable. A removal of the disturbing metallic ions with the aid of a cation exchanger was found to be the solution. An attempt was made, but without ultimate success, to exclude disturbing fluoride and silicofluoride.

The demands, which must be made in alkalimetric titrations on the purity of distilled water, have been sorted out and summarised.
Study of the molecular structure of cyclohexadiene −1,4 by the raman effect
Authors: Gerding H. , Haak F. A.
Published: September 2010

The Raman spectrum of liquid cyclohexadiene‐1,4, including polarization measurements and the infrared absorption bands in the spectral region 5.5–15 μ are communicated.

For this molecule a plane model with symmetry D2h and a “folded” one with symmetry C2v represent the more probable structures. A critical discussion of the Raman and infrared results makes it probable that the molecule possesses a configuration deviating only slightly from the rigorous D2h structure.

An assignment of the stronger Raman lines to vibrations of such a molecule is given.

Formulae were deduced for calculating the frequencies of the ring vibrations for a plane molecule as well as for the “folded” one, thereby making use of the known force constants for the C—C and CC bonds and of the C—C and CC distances found in the literature in comparable cases.

The results are: 463, 855 and 1720 cm−1 for D2h and 198, 470, 869 and 1695 cm−1 for C2v' compared with the frequencies 405, 858 and 1683 cm−1 of the strong and polarized lines in the region 0–1700 cm−1.
Structure and isomers of cyclohexane derivatives
Authors: Blekkingh J. J. A.
Published: September 2010

The structure of cyclohexane derivatives has been investigated by means of atom models. The non‐carbon‐carbon valency directions are indicated by the figures 1, 2, 3, 4, 5, 6 and 1′, 2′, 3′, 4′, 5′, 6′. The various isomers to be derived are characterized by the valency directions of the substituted hydrogen atoms. In general, every isomer can appear in 8 transition forms, viz. 2 immovable forms and 6 easily interchangeable forms.
The photodecomposition products of some diazonium salts
Authors: de Jonge J. , Dijkstra R.
Published: September 2010

By irradiation solutions of some benzene diazonium salts (including one p‐hydroxybenzenediazonium salt) in water the corresponding phenols could be isolated in a high yield.

The photodecomposition of two p‐diazo‐oxides seems to have a more complicated character.
Cétones dérivées de l'acénaphtène, du fluorène, et du dibenzothiophène
Authors: Buu‐Hoï Ng. Ph. , Cagniant Paul , Royer René
Published: September 2010

Dans ce travail, les auteurs décrivent les réactions de Friedel‐Crafts entre plusieurs chlorures d'acides aliphatiques d'une part, et d'autre part, les 3 hydrocarbures polycycliques suivants: acénaphténe, fluorène, et dibenzothiophène. De nombreuses cétones nouvelles ont ainsi été obtenues avec d'excellents rendements; celles dérivant du fluorène ont été oxydées en 2‐acylfluorénones. Les propriétés des corps nouveaux obtenus sont comparées avec celles déjà observées dans d'autres séries analogues (2‐alkylnaphtyl‐cétones, 3‐alkylthionaphténylcétones).
Synthesis of benzothiophenes
Authors: Werner E. G. G.
Published: September 2010

Four methylbenzothiophenes and two methylnaphthothiophenes were synthesized by cyclization of arylketosulphides (obtained by reaction of α‐halogen ketones on thiophenols) in the presence of zinc chloride or phosphorus pentoxide.

U.V. absorption spectra of the benzo and naphthothiophenes and their dioxides were measured to be used for the identification of benzothiophenes in mixtures with other compounds.
The vapour pressure of aqueous solutions saturated with lead nitrate and sodium nitrate: 20th Communication on saturated salt solutions
Authors: Dingemans P. , Dijkgraaf L. L.
Published: September 2010

The vapour pressure of the four phase equilibrium water vapour‐saturated solution‐solid Pb(NO3)2‐solid NaNO3 has been measured over the range of temperature 10°‐150° C.

It was found with this system, as also with systems of solutions, saturated with respect to one or more salts, previously determined that the relative vapour pressure as a function of the temperature is represented by a very weakly curved line.
The system NH4NO3NaNO3Pb(NO3)2H2O
Authors: Dingemans P. , Dijkgraaf L. L.
Published: September 2010

As an extension of the investigations previously published on the vapour pressures of aqueous solutions saturated with one or two of the salts NH4NO3, NaNO3 and Pb(NO3)2, the vapour pressure of the five phase equilibrium solid NH4NO3solid NaNO3solid Pb(NO3)2saturated solution‐water vapour has now been determined from 10° C to the end‐point of this line. This end‐point is the eutectic in the ternary system NH4NO3NaNO3Pb(NO3)2. We have determined this ternary eutectic. It was found to be situated at a temperature of 112.3 ± 0.1° C and a composition 62.7 per cent by weight of NH4NO3, 15.6 per cent NaNO3 and 21.7 per cent Pb(NO3)2.

The transition point γ → δ‐NH4NO3 causes a slight change in the slope in the vapour pressure curve at 84.2° C. The maximum occurring in the vapour pressure curve is situated at 85.9° C, thus at a temperature at which δ‐NH4NO3 is stable.

The relative vapour pressure, plotted as a function of the temperature, is seen for the system now investigated to be again represented by two almost straight lines, one valid for the temperatures below 84.2° C where γ‐NH4NO3 is stable and the other for the range 84.2°‐112.3° C where δ‐NH4NO3 is stable.

The formula previously published for the calculation of maxima in vapour pressure lines of saturated salt solutions, appears in this case also to give a value which agrees well with the experimentally determined one.