bluuebunny/crossref_metadata_2025 huggingface dataset:
Cis‐ and trans‐1,1‐diphenyl‐cyclopropane dicarbonic acid‐2,3: (Pyrazol and pyrazoline derivatives I)
Authors: van Alphen J.
Published: September 2010

The methyl esters of fumaric acid as well as of maleic acid combine with diphenyl‐diazomethane to give the same pyrazoline derivative, which upon being heated splits off nitrogen and gives the methyl ester of trans‐1,1‐diphenyl‐cyclopropane dicarbonic acid‐2,3. When maleic acid anhydride is made to combine with diphenyl diazomethane a compound is formed which splits off nitrogen rapidly at 80‐90° and slowly at ordinary temperatures, giving the anhydride of cis‐1,1‐diphenyl‐cyclopropane dicarbonic acid‐2,3.
On the basic nitrogen compounds from cracked distillates of californian petroleum
Authors: Hackmann J. Th. , Wibaut J. P. , Gitsels H. P. L.
Published: September 2010

From cracked distillates of Californian petroleum we isolated a mixture of basic nitrogen compounds distilling up to 125° at 1.5 mm. The part of this mixture of bases, which boiled up to 172.5° at 760 mm was examined very systematically, this mixture consists of homologues of pyridine. Next portion of boiling range 172.5‐215° at 760 mm also consists of homologues of pyridine; in this boiling range only three fractions were systematically examined.

The portion of boiling range 215° at 760 mm to 147.5° at 30 mm was again examined systematically. Besides pyridine homologues these fractions contain quinoline, isoquinoline and homologues of these compounds. The fractions boiling above 147.5° at 30 mm have not been examined; it is probable that these fractions contain numerous homologues of quinoline and isoquinoline.

We isolated in all 31 basic nitrogen compounds in the form of the picrates and (or) picrolonates. All these bases, except one, belong to the pyridine, quinoline, or isoquinoline type. The following compounds were identified: all possible isomers of the monomethyl pyridines and of the dimethylpyridines; 2.3.6 and 2.4.6 trimethylpyridine; 4‐ethylpyridine and three isomeric methyl‐ethyl pyridines in which the methylgroup occurs in the 2‐position (namely: 2,4‐ 2,5‐ and 2,6‐); 2‐ethyl‐4‐methylpyridine; quinoline, five isomeric methylquinolines (namely 2‐, 3‐, 4‐, 7‐, 8‐) and 2,8‐dimethylquinoline; isoquinoline; 1‐methyl‐ and 3‐methyl‐isoquinoline.

Besides these compounds of which the structure could be identified, five bases of yet unknown structure were isolated. The base C7H9N (b.pt. about 147°) and the two isomeric bases C8H11N (b.pt. 157.6 resp. 167.5) and the base C10H15N (b.pt. 188°) are probably pyridine homologues.

The base C11H15N isolated from the fraction boiling at 142.5‐145° at 30 mm is perhaps a trimethylpyrindane.

Details are given about the hydrogenation of the mixture of bases by chemical and catalytic methods.
The melting point diagram of the two‐component system diphenylamine‐acetamide
Authors: Vogels R. J. , Walop J. N.
Published: September 2010

The melting point curve of the binary system diphenylamine‐acetamide has been investigated.

The freezing line for the equilibrium Sacetamide ⇋ L has an inflexion point. Probably a metastable separation into two liquid phases would occur below the freezing line. In practice this separation itself has not been observed.
Sur la polymérisation du méthylchavicol et de l'éthylchavicol: Le 1,6‐di‐anisyl‐hexadiène‐1,5 et le 1,6‐di‐phénétyl‐hexadiène‐1,5
Authors: van der Zanden J. M.
Published: September 2010

Par la voie analytique et par la voie synthétique, nous avons déterminé la structure de deux produits, fondant respectivement à 166° et 156° et prenant naissance respectivement lors de la polymérisation sous l'action de la chaleur du méthyl‐ et de l'éthylchavicol. Contrairement à ce que l'on supposait, ce ne sont pas des dimères, mais des substances qui pourraient se former à partir de dimères par perte de deux atomes H. Il est possible que le dimère lui‐même ou le méthylchavicol fixent les deux atomes H.

En dehors des substances que nous avons mentionnées dans des mémoires antérieurs, nous avons synthétisé également le l,6‐di‐phénétyl‐l,2,5.6‐tétrabromo‐n.hexane, p. d. f. 181‐181.5°.
Δ1‐pyrazolines: (Pyrazol and pyrazoline derivatives II
Authors: van Alphen J.
Published: September 2010

Δ1‐pyrazolines, in which the double bond is situated between the two nitrogen atoms can be prepared by the addition of diphenyldiazomethane to the diphenyl ester of citraconic acid and to the trimethyl ester of aconitic acid. These compounds split off nitrogen at higher temperatures forming cyclopropane derivatives.

Diphenyl diazomethane combines directly with citraconic acid anhydride, splitting off nitrogen.
Wasserdampfdestillation
Authors: Schoorl N.
Published: September 2010

Besonderer Fall einer Destillation von ganz mit Wasser mischbaren flüchtigen Stoffen.
Wasserdampfdestillation
Authors: Schoorl N.
Published: September 2010

Ausbeute an flüchtigem Stoff bei der Dampfdestillation. (Ausbeutekurven).
De la Composition des acides gras de l'herbe, du foin et du trèfle rouge eu égard à leur influence sur la composition de la matière grasse du beurre
Authors: Brouwer E. , van Albada M.
Published: September 2010

On décrit brièvement une méthode pour isoler les acides gras des fourrages.

En appliquant cette méthode, on a constaté que pour la matière sèche du foin d'herbe, la teneur en acides gras et l'indice d'iode de ces acides sont beaucoup plus faibles que pour celle de l'herbe fraîche jeune et du trèfle frais jeune. Ces faits pourraient expliquer pourquoi l'indice d'iode de la graisse de beurre est plus faible sur une ration de foin que sur une ration d'herbe fraîche ou de trèfle rouge frais.
Sur les Polymères du méthylchavicol: Le 1,5‐dianisyl‐4‐méthyl‐pentène‐1
Authors: van der Zanden J. M.
Published: September 2010

En polymérisant le méthylchavicol sous l'action de la chaleur, nous avons pu isoler quelques produits cristallisés1). de deux de ces produits nous avons déterminé la structure. Après examen, nous avons constaté que ce sont le 1,6‐dianisylhexène‐12)

magnified image

et le 1,6‐dianisylhexadiène‐1,53)

magnified image

Nous avons entamé ensuite des recherches sur la structure du produit de p. d. f. 47°. Le dosage du carbone et de l'hydrogene, le dosage des groupes méthoxy et la détermination du poids moléculaire1) ont déjà démontré que, selon toute vraisemblance, nous avons affaire à un dimère du méthylchavicol.
Die Schmelzkurve des Systems MoO3‐WO3
Authors: Rieck G. D.
Published: September 2010

Die Schmelzkurve des Systems MoO3‐WO3 wurde teilweise mittels einer thermischen Untersuchungsmethode bestimmt.

Das durch Röntgenaufnahmen bestätigte Resultat ist, dass keine Mischkrystalle gebildet werden. Das Eutektikum liegt bei etwa 2 Mol.% WO3 und 765‐770° C.
On the use of the rotating step sector in combination with intermittent light sources in spectro chemical analysis
Authors: Schmidt R.
Published: September 2010

An account is given of the methods used in quantitative spectrochemical analysis, special attention being paid to the modern procedures using step weakeners: the “Zweilinienverfahren” and the Breckpot step sector method. The merits of both procedures are discussed, from which it follows that the sector method has some advantages over the former. Special problems, however, arise when the sector is used in combination with intermittent light sources (spark, interrupted arc). In this case stroboscopic effects are to be feared, which give rise to erratic values of the extinction caused by the sector. The only instance known in which the occurrence of such effects is claimed ‐ a paper by Pestemer and Schmidt ‐ is subjected to a mathematical treatment in order to check these claims. The results indicate that stroboscopic effects may indeed be observed, if only very conditionally, but that the experimental data on which Pestemer and Schmidt base the above mentioned claims are not in accord with the theoretical expectations. From these and other considerations optimum conditions for the use of the step sector in combination with intermittent light sources are derived, which are confirmed by experiment.
Die Abhängigkeit der Verdampfungswärme von der Temperatur
Authors: de Wijs J. C.
Published: September 2010

Eine von Eggert gegebene Beziehung zwischen Verdampfungswärme und Temperatur wurde an dem vorhandenen Zahlenmaterial geprüft und unrichtig befunden. Eine neuen Formel für diese Abhängigkeit, welche eine sehr gute Übereinstimmung zwischen beobachteten und berechneten Werten der Verdampfungswärme ergibt, wird vorgeschlagen.
Ableitung einer Dampfdruckgleichung aus der Temperaturabhängigkeit der Verdampfungswärme
Authors: de Wijs J. C.
Published: September 2010

Mittels der in der vorangehenden Abhandlung abgeleiteten Temperaturfunktion der Verdampfungswärme wird die Gleichung von Clausius‐Clapeyron integriert, was zu einer bekannten Dampfdruckgleichung führt. Die erhaltene Gleichung wird an Benzen und Wasser geprüft.
Die Wirkungsweise von Lokalanaesthetika bei der Epiduralinjektion
Authors: Numans S. R. , Havinga E.
Published: September 2010

In order to obtain an insight into the mechanism of epidural anaesthesia and into the permeability of membranes of the type of the dura mater spinalis for anaesthetics (and other physiologically active substances) generally, a method was worked out for the analysis of the spinal fluid of animals, which had previously been injected in the epidural space with a solution of novocain. Novocain was determined in the carefully collected samples of liquor by means of an extinctiometric method4). In addition it was identified by isolation as a picrate. In connection with some other experiments and with anatomical investigation, the results lead to the conclusion that the anaesthetic permeates very easily through the membranes which surround the spinal fluid. The significance for the interpretation of the mechanism of epidural anaesthesia is discussed and some related questions are pointed out.
Diènes Demi‐Cycliques et leur Application à la Synthèse de Composés Polynucléaires
Authors: Backer H. J. , van der Bij J. R.
Published: September 2010

Les diènes demi‐cycliques tels que les dérivés vinyliques du cyclopentène, du cyclohexène, du cycloheptène et du cyclooctène, soumis à des synthèses diéniques, engendrent des composés polynucléaires.

L'addition d'anhydride sulfureux aux diènes, donne naissance à des sulfones cycliques, qui s'isomérisent en solution alcaline. Les hydroanthraquinones qu'on obtient en faisant réagir les diènes sur la benzoquinone ou sur la naphtoquinone peuvent être transformées en anthracènes. On obtient ainsi des anthracènes qui portent des anneaux carbonés, soit dans les positions 1,2 et 5,6, soit en position 1,2 seulement.
On the moisture content and the condition of the milk sugar in Krause skim‐milk powder
Authors: Tamsma A. F.
Published: September 2010

Krause skim‐milk powder in air of 20, 30, 40 and 50% relative humidity takes up water resulting in final percentages of moisture of, respectively, 3.5, 4.8, 6.7 and 6.4%, calculated with respect to the powder at equilibrium. In the range 15°‐25°C the equilibrium does not change with the temperature.

These figures are about 1% higher than those of Supplee

G. C. Supplee, J. Dairy Sci. 9, 50 (1926).

) and about 0.4% lower than those of Davis

R. N. Davis, J. Dairy Sci. 22, 179 (1939).

).

Our data correspond exactly with the conclusion that in skim‐milk powder obtained by the usual Krause process the proportion of α‐ to β‐lactose is the same as in milk.

Another conclusion is that not all the lactose is in the anhydrous state, a result which differs from that of an investigation of Tillmans and Strohecker

J. Tillmans and R. Strohecker, Z. Untersuch. Lebensm. 47, 377 (1924).

). Extreme accuracy in determining the percentage of moisture is necessary in order to obtain reliable results. We worked out such a method suited to our purpose.
Dampfdruckbestimmungen an einigen organischen Stoffen
Authors: Cramer J. S. N.
Published: September 2010

Der Dampfdruck p eines Stoffes lässt sich bekanntlich aus der Verdampfungswärme mit Hilfe der Gleichung

In dieser Gleichung bedeutet W die Verdampfungswärme von 1 Grammolekül des Stoffes bei der absoluten Temperatur T und R die Gaskonstante.

In der vorliegenden Arbeit wurde der Dampfdruck von einigen organischen Stoffen bei verschiedenen Temperaturen bestimmt und aus den gefundenen Daten die Verdampfungswärme berechnet.
Researches on sulphanilamide derivatives. II. On 5‐sulphanilylamino‐tetrazole
Authors: Veldstra H. , Wiardi P. W.
Published: September 2010

The arguments of Jensen and Rosenlund Hansen

K. A. Jensen, O. Rosenlund Hansen, Rec. trav. chim.

) in support of their opinion that the tetrazoles described in our first paper

H. Veldstra, P. W. Wiardi, Rec. trav. chim. 61, 627 (1942).

) are not 5‐acetylsulphanilyl‐aminotetrazole (and 5‐sulphanilylaminotetrazole), but x‐acetylsulphanilyl‐5‐aminotetrazole (and x‐sulphanilyl‐5‐aminotetrazole) are considered unconvincing.

It is shown that the substances possess the structure we ascribed to them. It proves to be possible to isolate three tautomeric forms of 5‐acetylsulphanilylaminotetrazole.
On the haemolysing action of lysocithin
Authors: Gorter E. , Hermans J. J.
Published: September 2010

We have studied the haemolysing action of lysocithin on the chromocytes of man, rabbit and sheep. It was found that the amount of lysocithin needed to haemolyse a red cell is sufficient to cover this cell by a monomolecular layer. In view of the fact that lysocithin alters the shape (and therefore the surface) of the chromocytes before haemolysis sets in, no very accurate check is possible.

The lysocithin used was prepared from egg‐yolk. In a series of preliminary experiments with lyosocithin prepared from ovolecithin Merck the general features of lysocithin haemolysis were studied. It was shown that the number of chromocytes haemolysed by a given quantity of lysocithin is independent of the concentrations used. And further, that the process of lysocithin haemolysis is terminated within less than 15 minutes, even if insufficient lysocithin is present for the haemolysis to be complete.
Des Quinoléines Substituées. II. Synthèse de nouvelles 2‐arylquinoléines
Authors: Buu‐Hoï Ng. Ph. , Cagniant Paul
Published: September 2010

On décrit la méthode de préparation et les propriétés des quinoléines substituées en position 2 par des radicaux p‐cyclohexylphényl, p‐diphénylyl‐, α‐ et β‐naphthyl‐, 5‐acénaphtyl‐, 2‐anthryl‐, 3‐pyrényl‐, et 2‐chrysényliques.
On the resolution and properties of the mesoidic form of 1‐phenyl‐1,2‐diaminopropane
Authors: Froentjes W. , Dijkema K. M.
Published: September 2010

This paper describes a new method for the separation of the mesoidic and racemoidic form of 1,2‐diamines by means of the complex nickel tetrammine salts.
The crystal structure of sodium and ammonium iodate
Authors: Mac Gillavry C. H. , van Eck C. L. Panthaleon
Published: September 2010

Sodium iodate, described in the literature as an antiperovskite, has a coordination structure of sodium and iodate ions in deformed caesium chloride packing. The iodate ions have a pyramidal shape. Ammonium iodate, generally regarded as a true perovskite, very probably has the same structure.
Sur la Couleur et la Constitution de Quelques Dérivés Benzéniques Aminés I
Authors: Heertjes P. M. , Bakker R. , van Kerkhof J. C.
Published: September 2010

Dans cette publication sont donnés les spectres d'absorption de quelques dérivés benzéniques aminés et le comportement spectrographique de ces dérivés dans des solutions aqueuses acides. Ce travail fait partie d'une recherche sur le rôle joué par l'azote lors de son introduction dans les dérivés benzéniques. En outre, on trouvera dans cette publication une première étude des changements de constitution qui ont lieu lors de la formation des colorants du triphénylméthane par l'addition d'acide à une base carbinol.
Researches on adsorption electrodes VI. Glass electrodes. Influence of electrolytes on the potential of the glass electrode
Authors: Tendeloo H. J. C. , Voorspuij A. J. Zwart
Published: September 2010

After the discription of the experimental method, a theoretical deduction of the glas‐electrode function is given.

A new formula arrived at is generally in accordance with the measurements.
La constitution de la monobenzal‐d‐sorbite
Authors: van Der Laan P. J. , van der Mijll Dekker L. P.
Published: September 2010

Il s'est trouvé impossible de préparer le benzal‐1‐thréose par oxydation de la monobenzal‐d‐sorbite avec le tétra‐acétate de plomb. Par ce procédé on peut bien obtenir le benzal‐1‐xylose. Par réduction, cette substance donne un dérivé de la xylite, produit qui ne réagit pas avec le tétra‐acétate de plomb.

Se basant sur ces expériences, on a établi de nouvelles formules pour la monobenzal‐d‐sorbite et le monobenzal‐1‐xylose. Les formules répondent aux propriétés décrites dans la littérature.
Untersuchungen über Pilzfarbstoffe XIV : Über Oosporein, den Farbstoff von Oospora colorans van Beyma
Authors: Kögl F. , van Wessem G. C.
Published: September 2010

Aus Kulturen von Oospora colorans van Beyma wurde ein, in der Nuance an Mennige erinnernder Farbstoff der Zusammensetzung C14H10O8 isoliert, für den die Bezeichnung Oosporein vorgeschlagen wird. Die Konstitution konnte durch die Synthese bewiesen werden, welche über den strukturell nahe verwandten Pilzfarbstoff Phoenicin zum Oosporein führte.
Sur les Modifications de la Composition des Acides Gras de L'herbe Pendant la Maturation et la Conservation
Authors: Brouwer E.
Published: September 2010

Pendant la maturation de l'herbe, il s'effectue une diminution marquée de la teneur en acides gras de la matière sèche, tandis que le degré de non‐saturation de ces acides ne baisse que légèrement. Pendant le séchage artificiel de l'herbe et la conservation de l'herbe séchée, il se produit une destruction modérée des acides gras non saturés. Pendant le fanage et la conservation du foin, il se produit une destruction plus importante de ces acides. Toutes ces données sont parfaitement en accord avec l'hypothèse que la teneur en acide oléique de la graisse du beurre dépend en premier lieu des acides gras non saturés des fourrages.
The crystal structure and anisotropic temperature vibration of ammonium cyanide
Authors: Lely J. A. , Bijvoet J. M.
Published: September 2010

NH4CN crystallizes in a tetragonal structure. Cell dimensions: a = 4.16,c = 7.61 Å. space group: D104h‐P4/mcm. The atomic positions are given on p. 40, on which also a figure is seen showing the structure. This bears much resemblance to the CsCl‐structure of the other NH4‐halides. (The cell is doubled in the direction of the c‐axis by the orientation of the CN‐groups.

The CN‐groups oscillate in the planes (110) and (1¯10), respectively. This follows from the fact, that at room temperature intensity calculation of reflections with large third index, as compared with neighbouring reflections with small third index, give much too high results, the addition of an anisotropic heat factor yielding agreement between observed and calculated intensities both at room and low temperatures. The fact that the c‐axis increases considerably with temperature points to the same conclusion.
Die Bestimmung der Quantitativen Zusammensetzung von Mischungen, welche als Komponente Mahlprodukte von Roggen und Weizen enthalten, insbesondere mit Hilfe einer Nephelometrischen Methode. I: Mitteilung nr. 1 des Ausschusses für Brot und Brotgetreide der “Voedingsorganisatie T.N.O.”, bearbeitet in” “Het Station voor Maalderij en Bakkerij” te Wagingen
Authors: Hintzer H. M. R. , van der Lee J.
Published: September 2010

Nach einer Übersicht über die wichtigsten bekannten Methoden, wie diese in der Literatur beschrieben sind, wird die experimentelle Ausarbeitung einer nephelometrischen Untersuchungsmethode auf Grund des Unterschiedes im Gehalt an Trifructosan bet Roggen und Weizen gebracht.

Die Streuung im Trifructosangehalt sowohl bei Roggen als bei Weizen wird durch eine Reihe von Messungen an verschiedenen Roggen und Weizenrassen, wie auch an einigen Mühlenmustern von Mahlprodukten erläutert. Der Einfluss der Umstände, unter denen die Messung ausgeführt wird, wie Ausmahlungs‐ und Feinheitsgrad der Mahlprodukte, Temperatur usw., wird genau festgestellt.
Über das Nitrieren von n‐Octylbenzen
Authors: Rinkes I. J.
Published: September 2010

Nebenstehende Abhandlung enthält die genauen Angaben der physikalischen Konstanten von ortho‐, meta‐ und para‐Nitro‐n‐octylbenzen und die Ergebnisse der Nitrierung von n‐Octylbenzen.
Electrochemical behaviour of ion‐exchanging substances: I. Potential measurements on plant roots
Authors: Tendeloo H. J. C. , Vervelde G. J. , Voorspuij A. J. Zwart
Published: September 2010

According to the literature and to our own measurements the potential of plant roots is found to react sharply to the ion concentration of the medium around the roots. The roots of different plants behave as relatively good cation electrodes.

A scheme is proposed for describing the relation between root potential and ion concentration of the medium by the assumption of a Donnan equilibrium between the root and the medium. The root appears to act as a mixed electrode.
A kinetic investigation on the hydrolysis of simple aliphatic dicarboxylic tertiary butyl esters: Part II
Authors: Homan J. D. H.
Published: September 2010

This paper deals with the experimental data for the measurements mentioned in the preceding paper.

Some new compounds are described. The mathematical and experimental difficulties connected with the calculation of k1 for the ditert. butyl esters in dioxane‐water mixtures, could be met by a simple method of extrapolation.

The constants for the alkaline saponification of the first five tert butyl esters were determined; the values of k1 in water were deduced from those in dioxane‐water mixtures. Furthermore the rate constants for the acid hydrolysis of mono and ditert. butyl succinate were measured.

Upon comparing the data for the tert. butyl esters with those for the methyl and ethyl esters, the effect of the tert. butyl group generally appears to be in agreement with the supposition made in Part I.
Über den Einflusss von Gitterstörungen auf das Röntgendiagram, im Besonderen bei Gelen
Authors: Hermans J. J.
Published: September 2010

The influence of two extreme types of lattice distortions on the X‐ray diagram is demonstrated with the help of a simple one‐dimensional model. In the first type the displacements of the lattice points from their original positions are mutually independent, while in the second type of distortion a similar independence applies to the distance between successive lattice points. This second type gives rise to a broadening of reflexions, while the first does not.

The theory is further applied to a special type of lattice, viz. that where two lattice periods occur in statistical succession. This type of lattice may occur in many compounds. It is shown that it gives rise to a single interference at a Bragg angle corresponding to the average period defined by equation (17). In other words, the reflexion shows a continuous shift with varying amounts of the two components in the compound; a result which is, for instance, applicable to several examples of “intramicellar swelling”.
Forme des Cristaux et Vitesse de Croissance Lors de la Recristallisation Primaire de L'Aluminium
Authors: Burgers W. G.
Published: September 2010

Le but de la présente note est d'attirer l'attention sur une particularité de la forme des lignes de séparation des cristaux dans de l'aluminium récristallisé, qui peut se présenter si l'on admet l'existence de différences réelles dans la vitesse de croissance des cristaux adjacents.
Eine Kolorimetrische Bestimmung des Atropins
Authors: van Os F. H. L.
Published: September 2010

Es wurde ein Verfahren zur schnellen Bestimmung kleiner Mengen von Atropin ausgearbeitet, beruhend auf der Bildung eines Kupplungsproduktes mit p‐Dimethyl‐aminobenzaldehyd in 90 %‐Schwefelsäure (Wasicky's Reagenz). Dazu wird der Farbstoff in Essigsäureanhydrid gelöst und im Pulfrich‐Photometer oder im Kolorimeter gemessen.

Ferner wurde das Absorptionsspektrum der Farbstofflösung bestimmt und gezeigt, dass dieses Spektrum grosse Übereinstimmung aufweist mit dem einer salzsauren Kobaltchloridlösung, was eine einfache kolorimetrische Bestimmung ermöglicht.
On the results obtained with a large scale apparatus for the bromination of pyridine in the gas phase: (58th communication on derivatives of pyridine and quinoline)
Authors: Wibaut J. P. , den Hertog H. J.
Published: September 2010

An apparatus is described for the bromination of pyridine in the gas phase on a larger scale, the preparation with this apparatus of 3‐bromopyridine and the influence of changes in the reaction conditions on this bromination.

By heating the reaction product of brominations carried out at 300° with ammonia, 2‐ and 4‐aminopyridine among other products are obtained. From this fact, and from the isolation of various higher substituted bromopyridines, it appears that at 300°, besides the hydrogen atoms at positions 3 and 5, those at positions 2, 4 and 6 are also able to enter into reaction.

Some brominations with this apparatus, at 200° and 500° are discussed.
Sur la Copulation de Certaines Pyrazolones Avec les Diazocomposés Aromatiques
Authors: Verkade P. E. , Dhont J.
Published: September 2010

La 3,4‐diméthyl‐pyrazolone‐(5) et la 3‐phényl‐4‐méthyl‐pyrazolone‐(5) se copulent avec les diazocomposés aromatiques en formant des substances ayant le caractère de composés diazoaminés. Le groupe benzèneazo ne se trouve pas en position 4, mais est lié à un des atomes d'azote du noyau pyrazolonique, très vraisemblablement en position 2. Il n'est done pas question ici d'exceptions à la “règle” que la copulation en position 4 n'a lieu que si, après énolisation de la triade formée par les atomes de carbone 4 et 5 et l'atome d'oxygène, il reste encore un atome d'hydrogène en position 4.
On the influence of naphthoquinones on the respiration and light emission of photobacterium phosphoreum
Authors: Spruit C. J. P. , Schuiling A. L.
Published: September 2010

The influence of various naphthoquinones on the light emission and respiration of Photobacterium phosphoreum has been studied. Minute amounts of some of these compounds strongly inhibited the light emission. It appeared that this inhibition was connected with the redox potential of the quinones used and due to a dehydrogenating action of the naphthoquinones on the luciferin or on a hydrogen donator ultimately active in the formation of this compound. Since KCN eliminates the inhibition of the naphthoquinones, we concluded that the naphthohydroquinones formed were dehydrogenated again with the aid of a KCN‐sensitive catalyst. These observations give rise to a modified scheme for the respiration of the luminous bacteria.
Die Diffusion in Wolfram mit Niedrigem Eisengehalt
Authors: v. Liempt J. A. M.
Published: September 2010

Messungen der Diffusion in Wolfram mit 0.04% Eisen durch Bestimmung des Eisenverlustes in Eisenhaltigen Wolframdrähten beim Glühen in Hochvakuum. Für die Berechnung der Diffusions‐Koëffizienten wurde eine früher abgeleitete Annäherungsformel benutzt, die praktisch die gleichen Ergebnisse liefert wie eine andere, von Dünwald und Wagner abgeleitete Annäherungsformel.

Der gegenseitige Diffusionskoëffizient erweist sich darstellbar durch die Formel

D (cm2/sec) = 11.5e−71667/T

Die Diffusionswärme beträgt 140000 g‐cal pro g‐Atom. Es wird gezeigt, dass diese Formel vermutlich auch annähernd die Selbstdiffusion von Wolfram darstellt.

Ganz allgemein wird auf die Wahrscheinlichkeit hingewiesen, dass die Kurve der gegenseitigen Diffusionskoëffizienten in einem binären System und im Mischkrystallgebiet, wenigstens bei Substitutions‐Mischkrystallen, in den Wert für die Selbstdiffusionskoëffizienten des einen oder gegebenen Falles beider Komponenten auslaufen muss, sodass sich dadurch eine neue Möglichkeit bietet, um die Selbstdiffusion angenähert zu messen. Es wird die Möglichkeit diskutiert, dass in der Nähe der reinen Komponenten ein unerwartet steiler Verlauf eintritt. Vorgeschlagen wird der Gebrauch der Ausdrücke “gegenseitiger Diffusionskoëffizient” und “Diffusionskoëffizient” für die Diffusion in Substitutions‐Mischkrystallen bzw. in “Einlagerungs”‐Mischkrystallen.
Untersuchungen über Indolderivate: V. Nitroso‐derivate von Indolen
Authors: Verkade P. E. , Lieste J. , Werner E. G. G.
Published: September 2010

Es wird das Verhalten von verschiedenen Typen von Nitrosoderivaten von Indolabkömmlingen (Nitrosaminen, Isonitroso‐ und Nitrosoverbindungen) gegenüber Kalilauge und bei der Liebermann'schen und der Diphenylaminreaktion beschrieben. Das entwickelte Schema ist brauchbar für die Ermittelung der Konstitution von vielen Indolderivaten und bisweilen auch für die Trennung von Gemischen solcher Verbindungen.
Ultramikroanalyse III: Uber eine Methode zur Anreicherung von Kupfer durch selektive Adsorption und über die Zerstörung von organischem Material zur Kupferbestimmung
Authors: Seekles L. , Havinga E. , Bijkerk R.
Published: September 2010

A description is given of a simple and convenient method for the destruction of organic material by preliminary treatment with conc. nitric acid, followed by boiling with conc. sulphuric acid. This method enables a direct measurement of the copper content in animal and vegetable materials (liver, grass etc.).

Copper ions could be concentrated out of very dilute solutions by filtering the solution through cotton wool which had been previously “conditioned” by drenching it with an alcoholic solution of sodium stearate, followed by drying. This adsorption method could be applied to solutions obtained by destruction of organic materials only after a strong final oxidation by potassium periodate. According to this observation organic acids, such as glycine and citric acid, were shown to interfere with the adsorption of copper ions by stearate. Obviously some organic substances of lower molecular weights are not destroyed in the ordinary way by means of nitric and sulphuric acid.
Contribution a la Chimie de L'α‐Naphtyl‐Acetonitrile
Authors: Buu‐Hoï Ng. Ph. , Cagniant Paul
Published: September 2010

Dans ce travail, les auteurs apportent une contribution à la Chimie de l'α‐naphtyl‐acétonitrile, décrivant en particulier des réactions d'alcoylation au moyen de l'amidure de sodium. Les nitriles ainsi obtenus permettent d'accéder aux acides α‐naphtyl‐acétiques substitués correspondants; les esters de ces derniers corps avec les amino‐alcools sont parfois doués de propriétés physiologiques intéressantes (activités spasmolytique ou anesthésique). Enfin, la question de l'empêchement stérique dans la saponification des nitriles α‐naphtyl‐acétiques est discutée.
The mean polarizability of dipole molecules in the direction of an external electrical field
Authors: Böttcher C. J. F.
Published: September 2010

It is shown that even for pronouncedly anisotropic dipole molecules the mean polarizability in a homogeneous external electrical field, provided there is no saturation, is practically equal to (α1 + α2 + α3)/3 where α1, α2 and α3 are the polarizabilities in the three main directions.
A differential method for the calculation of the mean radius of particles
Authors: Böttcher C. J. F.
Published: September 2010

A differential formula is derived, with the aid of which it is possible to compute the mean radius of the particles of a substance whose density and refractive index are known at different values of the temperature or of the pressure.
Calculation of the index of‐refraction of an aggregate of particles
Authors: Böttcher C. J. F.
Published: September 2010

From some examples it will be shown that it is possible with the aid of a formula derived by the present writer to compute with a high degree of accuracy the index of refraction of an aggregate from the radii and the polarizabilities of the particles of which it is composed.
Essais de préparation du tetrakis‐méthyl‐sulfonyl‐méthane
Authors: Backer H. J.
Published: September 2010

L'oxydation prudente du tétrathioorthocarbonate de méthyle ne donne pas la tétrasulfone correspondante, mais une trisulfone, le tris‐méthylsulfonyl‐méthane. Nous avons essayé d'introduire dans cette trisulfone un quatrième groupe méthylsulfonyle ou un groupe thioéther, que l'on pourrait oxyder ensuite. La réaction du méthylmercaptide et du chlorure méthylsulfonique sur le bromo‐tris‐méthylsulfonyl‐méthane a régénéré la trisulfone. La réaction entre un sulfinate d'argent et le dérivé sodique de la trisulfone n'a pas donné non plus le résultat désiré.
The reaction between α‐halogenoketones and phenylhydrazine. III
Authors: van Alphen J.
Published: September 2010

The reaction between some α‐halogenoketones and phenylhydrazine has been investigated. It appears that compounds with a conjugated system of a C:C and a N:N double bond are obtained only when the carbonyl group does not stand adjacent to a phenyl group.
Raman effect study of the two hexachloroketocyclopentenes C5Cl6O
Authors: van Brederode H. , Gerding H. , Prins H. J.
Published: September 2010

The Raman frequency shifts of the two isomeric ketones C5Cl6O of melting points 28° and 92°, described for the first time by Zincke and Küster in 1888, were determined by a study of the Raman spectra of the undercooled liquid 28° isomer, the molten 92° isomer and of solutions of both of them in carbon tetrachloride as well as in carbon disulphide. Polarization measurements for liquid 28° and for solutions of the 28° and 92° isomers in CCl4 were also performed.

Accelerated by the illumination, the molten 92° ketone shows an appreciable transformation in the direction of the equilibrium mixture corresponding to 28° in excess at that temperature. In undercooled liquid 28° the transformation is of subordinate degree at room temperature, even after long‐continued illumination.

In the solutions no conversion took place to any measurable extent, as was proved by melting point determinations of the solids obtained by evaporation of the solvent after the Raman effect study.

There are distinct differences between the Raman spectra of the two isomers. The Raman results do not agree either with possible open‐chain compounds of formula C5Cl6O, or with formulae containing heterocyclic six‐rings built up of five carbon atoms and one atom of oxygen. No simple decision can be reached between possible structures with four‐membered rings and the five‐ring formula accepted by Zincke and Küster on chemical grounds, when only the purely physical facts are considered.

The Raman results (frequency heights, polarization results) agree best with cyclical structures with plane rings for both ketones, the 28° ketone corresponding to the less symmetrical structure II

magnified image with a conjugated system of double bonds C = C with C = O, and the 92° ketone having the more symmetrical structure I. magnified image

From the incomplete determinations of the composition of the equilibrium 28° ⇆ 92° in the liquid state at three temperatures by Küster, it follows that the 28° isomer possesses the lower energy content. The energy difference can be ascribed mainly to the extra resonance energy in the 28° ketone, caused by the conjugation of the double bonds C = C and C = O, which is also an argument for the structure II for the 28° form.
Untersuchungen über Indolderivate VI.: Die Reaktion Zwischen Monobromaceton und Primären und Sekundären Aromatischen Aminen
Authors: Janetzky E. F. J. , Verkade P. E. , Lieste J.
Published: September 2010

Die Reaktion zwischen Monobromaceton und primären aromatischen Aminen verläuft abnormal; es bilden sich nicht die zu erwartenden α‐Arylaminoketone, sondern Produkte von doppeltem Molekulargewicht.

Mit sekundären aromatischen Aminen verläuft die Reaktion in üblicher Weise. Untersucht wurde besonders die Einwirkung von Monomethyl‐ und Monoäthylanilin, wobei mit sehr guter Ausbeute Phenylmethylamino‐propanon bzw. Phenyläthylamino‐propanon erhalten wurde. Durch Erhitzen mit 11/2% ihres Gewichtes an Zinkchlorid gingen diese Substanzen glatt in 1,3‐Dimethylindol bzw. 1‐Äthyl‐3‐methylindol über. Es handelt sich bei diesen Reaktionen um wahre Ringschliessung.

Ausgehend von N‐Methyl‐p‐anisidin und Monomethylanilinhydrochlorid konnte mit sehr befriedigender Ausbeute 1,3‐Dimethyl‐5‐methoxyindol (Physostigmolmethyläther) erhalten werden.
The determination of uranium with o‐oxyquinoline
Authors: Claassen A. , Visser J.
Published: September 2010

Hecht and Reich‐Rohrwig's method for the determination of uranium by means of o‐oxyquinoline was subjected to a critical investigation. It was found that washing the precipitate with hot water, as prescribed in the original procedure, leads to heavy losses, which can be prevented by washing with a hot 0.04% oxine solution. Precipitation is complete at a pH between 5.0 and 9.0. The proposed procedure gives results which are about 0.2% too low when calculated with the theoretical conversion factor. Ignition of the oxinate to U3O8 gives results accurate within 0.1%. Tartrates do not prevent quantitative precipitation. The separation of U from magnesium, the alkaline earths and from alkali metals is complete.
Über Die Konfiguration des Glutathions aus Tumoren: II. Mitteilung über die Chemie der Tumoren
Authors: Kögl F. , Akkerman A. M.
Published: September 2010

Es wurde festgestellt, dass Epi‐g‐glutathion als Aktivator der Glyoxalase fungieren kann; es besitzt etwa 65% der Aktivität des natürlichen Glutathions.

Bei der Bestimmung des Glutathion‐Gehalts von Tumoren gibt das manometrische Verfahren von Woodward niedrigere Werte als die jodometrische Methode von Waelsch und Rittenberg; bei normalen Geweben wurde dieser Unterschied nicht gefunden.

Lösungen von Cupro‐glutathion in 1.4 n Salzsäure zeigen eine konstante Drehung; die in der Literatur beschriebene Mutarotation beruht auf der bei Luftzutritt erfolgenden Oxydation zum Disulfid.

Das aus 14 malignen Tumoren und aus 2 Uterusmyomen als Cuproverbindung isolierte Glutathion zeigte praktisch die gleiche spezifische Drehung wie die aus normalem Gewebe erhaltenen Präparate. An Tumorbrei zugefügtes Epi‐g‐glutathion liess sich durch die Depression der Drehung des isolierten Cupro‐merkaptids nachweisen.
Sur la synthèse et les propriétés de certaines aryl‐benzyl‐cétones
Authors: Buu‐Hoï N. G. Ph. , Royer René
Published: September 2010

Dans le présent travail, on décrit toute une série de réactions de Friedel‐Crafts entre le chlorure de phénylacétyle d'une part, et d'autre part, de nombreux composés aromatiques appartenant aux noyaux benzénique et naphtalénique. Plusieurs aryl‐benzyl‐cétones nouvelles ont été ainsi préparées, leur constitution établie, et leurs principales propriétés chimiques indiquées. Subsidiairement, la structure d'un corps obtenu autrefois par Mac Kenzie et Tattersall à partir de l'acide phényl‐a‐naphtyl‐acétique a pu être éclaircie.
The purification of carbon rods for spectrochemical analysis
Authors: Deinum H. W.
Published: September 2010

The maximum temperature was measured to which a carbon conductor can be heated by direct passage of current. The influence of the dimensions of the conductor was investigated. An explanation was given of the frequently observed explosion.
The basic amino acids, purine bases and pyrimidines of protein‐free grass extracts
Authors: de Man Th. J.
Published: September 2010

The nitrogen compounds of low molecular weight of protein‐free extracts from one of the most important pasture grasses, Lolium perenne, were investigated. Adenine could be isolated as a picrate and arginine as a flavianate from a fraction obtained by a treatment with mercuric acetate and sodium carbonate and a subsequent precipitation with phosphotungstic acid.

After hydrolysing the protein‐free extract in order to split the peptides present, in addition to the above mentioned compounds lysine could be isolated as a picrate and a flavianate from the histidine fraction.

This flavianate proved not to be a histidine diflavianate, but micro‐analysis showed that it had the composition of cytosine flavianate. The occurrence of cytosine in Lolium perenne was proved and the occurrence of lysine as a building stone of peptides is discussed.

The purine fraction obtained with the aid of ammoniacal silver nitrate was investigated; besides adenine, we were not able to isolate other purine bases from this fraction.
Researches on the alkoxy‐amino‐nitrobenzenes II. Synthesis and taste of the ten possible ethoxy and n‐propoxy compounds. Some remarks concerning the problem of the relation between taste and constitution
Authors: Verkade P. E. , Witjens P. H.
Published: September 2010

The preparation of the ethoxy and n‐propoxy compounds of the types III‐X (see below) is described. The aqueous solutions of the substances of type IV taste faintly bitter; the substances of the other seven types possess no appreciable taste.

In communication I of this series it was shown that the corresponding compounds of type I have a very pronounced sweet taste, whereas those of type II are tasteless.

On the basis of these facts some problems concerning the relation between taste and constitution of organic compounds are discussed.
On the reactions of acid chlorides and acid anhydrides with the lithium compounds of 2‐methylpyridine and 2,6‐dimethylpyridine
Authors: Kloppenburg C. C. , Wibaut J. P.
Published: September 2010

In the action of acetic anhydride on picolyl lithium (I) the by‐product 1,3‐bis‐(2‐pyridyl)‐2‐methylpropanol‐2 (III) is formed in addition to α‐picolylmethylketone (II); in the action of acetyl chloride on I it depends upon the conditions of the experiment whether the main product will be II or III. In the action of benzoic anhydride on I α‐picolylphenylketone (IV) is formed and a small amount of (2‐pyridyl)‐dibenzoylmethane (V). According to the conditions of the experiment the action of benzoylchloride on I gives mainly IV or a base containing no oxygen: 1,3‐bis‐(2‐pyridyl)‐2‐phenylpropene (IX). In the action of phenyl lithium and benzoic anhydride on lutidine 6‐(2‐picolyl)‐dibenzoylmethane (XVII) is formed.
The ozonization of 2,3‐dimethylnaphthalene; and of 1,4‐dimethylnaphthalene. a contribution to the problem of the bond structure of naphthalene
Authors: Wibaut J. P. , van Dijk J.
Published: September 2010

By the ozonization of 2,3‐dimethylnaphthalene are formed glyoxal, methylglyoxal and dimethylglyoxal; these compounds have been identified by means of the oximes.

The relative amounts of these oxidation products have been determined, the molecular ratio of dimethylglyoxal to methylglyoxal is about 1 : 0.1. By the ozonization of 1,4‐dimethylnaphthalene are formed glyoxal and methylglyoxal; the relative amounts of these oxidation products have been determined, the total yields are low.

The experimental evidence obtained does not support the assumption made by Marckwald, Fries, Fieser and other chemists, that naphthalene and its derivatives have the symmetrical structure (Erlenmeyer‐Graebe structure) and that the single and double bonds between the carbon atoms of the bicyclic system are incapable of migrating.

The experimental results can be interpreted in the simplest way by the assumption that 2,3‐dimethylnaphthalene can react according to the three mesomeric forms and that 1,4‐dimethylnaphthalene can react according to an unsymmetrical structure (Erdmann structure). It remains undecided whether 1,4‐dimethylnaphthalene can also react according to the symmetrical structure; however, the assumption that 1,4‐dimethylnaphthalene can react according to the three mesomeric forms is not contradictory to the observed facts.
The carbon‐chlorine bond in the chloronaphthalenes
Authors: Ketelaar J. A. A. , van Oosterhout G. W.
Published: September 2010

The dipole moments of 1 and 2‐chloronaphthalene are discussed by the method of molecular orbitals. If an “effective” electron charge is assumed in agreement with the dipole moment of 1‐chloronaphthalene, the moment of 2‐chloronaphthalene can be calculated in complete agreement with the experimental value.

The calculated energy levels are in nearly quantitative agreement with the long‐wave limits of U.V. absorption of the two compounds. From the calculation follow the values 14.2% and 13% for the double‐bond character of the C‐Cl bond in 1 and 2‐chloronaphthalene, respectively. Starting from this result the acid and basic strengths of the naphtholes and the naphthylamines are discussed by consideration of a very simple valence bond scheme.
Electrochemical behaviour of ion‐exchanging substances: II. Potential measurements on plant roots and their bearing on ion uptake by plants
Authors: Tendeloo H. J. C. , Vervelde G. J. , Voorspuy A. J. Zwart
Published: September 2010

Assuming that the non‐diffusible ion in the theory of the Donnan equilibrium originates from a substance which behaves as a weak acid, the concentration of its anion being therefore not constant but depending on the pH, a fairly good agreement could be detected between the calculated and the experimentally found figures for the potentials of plant roots.

Some considerations based on the Donnan principle, concerning the intake of ions by plants from different solutions are in agreement with practical results on plants grown in the field and in culture solutions. It seems likely that the first stage of the intake of ions by living plants, viz. the passage of ions through the root wall, may be understood with this theory of the Donnan equilibrium.
Movement of uncharged particles and molecules in the electric field
Authors: Janssen L. W.
Published: September 2010

The movement of molecules of sugar in the electric field in different solutions of electrolytes is studied in the electrophoresis apparatus of Tiselius and with a modified optical arrangement according to Philpot‐Svensson. It is found that under such conditions uncharged molecules move.

The velocity of the sugar molecules is dependent on the strength of the field and on the nature of the ions which are present. The new effect is not due to electroendosmosis, transport of water or electrode phenomena; but originates actually from the kinetic energy of the ions transporting the current. Often the influence of the anions predominates causing an anodic movement of the sugar.

Especially in the case of stronger fields the ions crossing the boundaries produce well defined distortions of the boundaries clearly visible with the used optical technique.

If uncharged particles can in fact move in the electric field, the results of the investigation of the movement of charged particles, the electrophoresis, ought to be corrected for this new electrokinetic phenomenon.
Étude des solutions colloïdales par des mesures de viscosité et de densité optique
Authors: Boutaric Augustin
Published: September 2010

Sous diverses influences ou même spontanément les solutions colloïdales sont le siège de transformations se traduisant par une variation de volume de leurs particules. Nous voudrions dans cet exposé appeler l'attention sur les renseignements que permettent d'obtenir les mesures de viscosité et de densité optique et indiquer les résultats ainsi obtenus dans l'étude des solutions colloïdales.
Electrokinetics XXVII. The electroviscosity effect
Authors: Briggs D. R.
Published: September 2010

A review is given of some studies carried on in an attempt to test the veracity of the Smoluchowski equation for the electroviscosity effect.
Relaxation effects in stretched cellulose model filaments. I. Relaxation of Retractive Force
Authors: Hermans J. J.
Published: September 2010

If cellulose model filaments are stretched at a moderate rate and then kept at constant length, the retractive force relaxes to a finite value, which is roughly 1/2 of the initial force at the moment relaxation sets in. Both this initial force before and the final force after relaxation are independent of whether the fibre is stretched to the elongation studied in subsequent stages or directly.
Relaxation effects in stretched cellulose model filaments II. Relaxation of double refraction
Authors: Vermaas D.
Published: September 2010

Highly swollen fresh cellulose model filaments, when kept at constant length after having been stretched, show an increase in double refraction and a decrease in degree of swelling with time. Reswollen filaments exhibit a decrease in double refraction at relatively low stretch and an increase at high elongation, the degree of swelling remaining constant in the former case and decreasing in the latter. A tentative explanation is given for these variations in double refraction.