bluuebunny/crossref_metadata_2025 huggingface dataset:
Stability of oil‐in‐water emulsions III: Measurement of the rate of coagulation of an oil‐in‐water emulsion
Authors: van den Tempel M.
Published: September 2010

Dilute oil‐in‐water emulsions stabilised with anionic soaps were coagulated by the addition of salt. After a predetermined time coagulation was stopped by diluting with a solution of a nonionic surface active agent. The rate of coagulation was measured by counting, after varying times of coagulation, the number of oil drops under a microscope.

The rate of coagulation increases with increasing salt concentration. An upper limit in the rate of coagulation, where “rapid” flocculation occurs, was observed when salts with polyvalent cations were used as the coagulating electrolyte.

Increasing the concentration of Aerosol OT caused a higher rate of coagulation in dilute salt solutions and a lower rate at higher salt concentrations. Variation of the concentration of the more soluble soaps had little effect on the rate of coagulation.

The influence of the valency of the coagulating cation was investigated in emulsions stabilised with a soap giving no insoluble compounds with the cations used. A behaviour as predicted by the rule of Schulze and Hardy was observed. Variation of the anion in the coagulating electrolyte had no effect on the rate of coagulation.

The rate of coagulation decreases with increasing initial particle concentration. This is explained by considering coagulation as caused by flocculation followed by coalescence. From experiments in which the initial particle concentration was varied, estimations could be made of both the rate of flocculation and of coalescence. The rate of coalescence had a value of the order of 0.001 per second. For the rate of flocculation a higher value was found than that predicted by Von Smoluchowski's theory for “rapid” flocculation. Several effects are present which operate simultaneously to increase the measured rate of flocculation; the influence of these effects is discussed.
Syntheses with the aid of γ‐picolyllithium II: Preparation of oxygen‐containing derivatives
Authors: Hey J. W. , Wibaut J. P.
Published: September 2010

β‐(Pyridyl‐4′)‐propionaldehyde‐diethylacetal (II) is obtained in a yield of 39% by the action of bromoacetal on γ‐picolyllithium (I). By allowing I to react with acetyl bromide or with ethyl acetate, a 34% yield of (pyridyl‐4′)‐propanone (III) is obtained. By the action of carbon dioxide on I, (pyridyl‐4′)‐acetic acid is prepared, which is isolated as the ethyl ester (IV) (yield 34%).
Preparation of thio‐orotic acid labelled with S35
Authors: Ernsting M. J. E. , Nauta W. Th.
Published: September 2010

It was found that condensation of thiourea with ethyl ester of oxalacetic acid in an alkaline milieu yields a higher quantity of thio‐orotic acid than the methods described in the literature. This method of condensation was applied to the preparation of thio‐orotic acid labelled with S35.
The determination of microgram quantities of mercury
Authors: Melles J. L. , de Bree W.
Published: September 2010

The existing methods for the micro‐determination of mercury have not given reliable results for the determination of this metal in spray residues on the leaves of apple and pear.

As most methods are complicated, simple methods for the destruction of the plant materials and for the separation of the mercury have now been developed.
Nouvelle synthese d'esters thiolsulfoniques: Reaction d'anhydride sulfureux sur le diphenyldiazomethane en presence de mercaptannes: (Propriétés du groupe sulfonyle XXXVII
Authors: Kloosterziel H. , Boerema J. S. , Backer H. J.
Published: September 2010

La réaction conduit à des thiolsulfonates (“disulfoxydes”) de la formule (C6H5)2CHSO2SR. On peut admettre une fixation des mercaptannes sur la double liaison d'un “sulfène” formé intermédiairement.
The synthesis of p‐guanidino‐salicylic acid and some related compounds
Authors: Beyerman H. C. , Bontekoe J. S.
Published: September 2010

The syntheses of 4‐guanidino‐salicylic acid, 4‐(N′‐cyanoguanidino)‐ salicylic acid, and some related compounds are described.

Intermolecular coupling of the diazonium salt of ρ‐amino‐salicylic acid and of its methyl ester yielded products which are in all probability 2,4,3′‐trihydroxy‐5,4′‐dicarboxy‐azobenzene and the methyl ester thereof.

These and some related compounds were prepared in order to examine their possible growth‐inhibiting properties for Mycobact. tuberculosis.
A theoretical treatment of Hammett's sigma constants
Authors: Sixma F. L. J.
Published: September 2010

A theoretical treatment is given of the connection between the structure and the position of a substituent S and the value of σs, from the Hammett equation: log ks/ko = ρ · σs. The theory is based on a wave mechanical calculation of the effect of S on the localisation energy of a reaction. The equations derived make it possible to calculate σs, for a large number of substituents from known values of bond lengths and bond moments.

The calculations are carried out for a number of different reaction types, which are representative of a large number of reactions. The mean deviation of the theoretical values of σ from the experimental values amounts to ±0.07; the agreement reached is of the same order, therefore, as the experimentally found deviations from Hammett's equation.
The relationship between the work function of a metal and its energy of activation for oxidation
Authors: Ward A. F. H. , Bharucha N. R.
Published: September 2010

It has been shown that there is a very highly significant correlation coefficient between the work function (Φ) of metals and the activation energy for oxidation (E). The values of Φ‐E tend to decrease slightly with increase in the atomic number.
Vinylogie chez les composés de sulfonyle I: (Propriétés du groupe sulfonyle XXXIX)
Authors: Backer H. J. , Strating J. , Hazenberg J. F. A.
Published: September 2010

Le 1,2‐dichloro‐1‐tertiobutylsulfonyl‐éthène, qui peut être regardé comme vinylogue d'un sulfochlorure, dispose d'un atome de chlore qui est extrêmement actif. Tout comme un sulfochlorure, ce composé réagit avec les alcools, les mercaptannes etc. Les produits se comportent comme les vinylogues des simples composés sulfonylés correspondants.
Synthesis of polychloro compounds with aluminium chloride XIII. The condensation of formaldehyde, symm.‐dichlorodimethyl ether, and chloromethyl methyl ether with trichloroethene and with tetrachloroethene
Authors: Prins H. J.
Published: September 2010

The condensation of formaldehyde (paraformaldehyde or trioxane) with trichloroethene in the presence of aluminium chloride gives a mixture of 2,3,3,3‐tetrachloropropanol‐1, the di‐ether of this alcohol (2,3,3,3,2′,3′,3′,3′‐octochloro‐di‐n‐propylether), and αβ‐dichloropropionyl chloride.

The same di‐ether is obtained by the condensation of symm.‐dichlorodimethyl ether with trichloroethene.

Condensation of chloromethyl methyl ether with trichloroethene gives the methyl ether of 2,3,3,3‐tetrachloropropanol‐1.

Tetrachloroethene yields, by condensation with formaldehyde, 2,2,3,3,3‐pentachloropropanol‐1 and the di‐ether of this alcohol (2,2,3,3,3,2′,2′,3′,3′,3′‐decachloro‐di‐n‐propylether).

The same ether results from the condensation of tetrachloroethene with symm.‐dichlorodimethyl ether.

At temperatures above 50°, cleavage and dehydrohalogenation of the di‐ether of 2,2,3,3,3‐pentachloropropanol‐1 occurs, with formation of 1,1,2,3,3‐pentachloropropene‐1 as well as 2,2,3,3,3‐pentachloropropanol‐1.

Condensation of chloromethyl methyl ether with tetrachloroethene is accompanied by cleavage of the ensuing methyl ether of 2,2,3,3,3‐pentachloropropanol‐1, and yields 2,2,3,3,3‐pentachloropropanol‐1.

The mechanism of these reactions is discussed.
On the paper chromatography of α‐glyceryl ethers
Authors: Emmerie A.
Published: September 2010

Some α‐glyceryl ethers present in cod‐liver oil have been converted into the corresponding aldehydes by oxidation with periodic acid. These aldehydes have been separated by paper chromatography.
4‐Aminofluorene
Authors: Neish William J. P.
Published: September 2010

A synthesis of 4‐aminofluorene from 4‐nitrophenanthraquinone is described. Ultraviolet absorption spectra of 4‐aminofluorene and 2‐aminofluorene are recorded.
The binary system of nitrosyl chloride with aluminium chloride
Authors: Houtgraaf H. , de Roos A. M.
Published: September 2010

The fusing point diagram of NOCl with AlCl3 has been investigated.

The curves show a well defined maximum at a composition of 1 mole of NOCl and 1 mole of AlCl3. The congruent melting point of the compound NOCl · AlCl3 has been determined as 180° C. In high vacuum this compound can be sublimed almost undecomposed.

Another compound with an incongruent melting point has been found. containing 2 moles of NOCl and 1 mole of AlCl3 (transformation point 17.5° C).

Moreover there exists a two liquid layer region extending from about 84 mole % of AlCl3 to about 99 mole % of AlCl3. (The temperature of the three‐phase equilibrium S + L1 + L2 is about 195.2° C).

Some attention is paid to the difficulties encountered in the determination of the exact melting point temperature of solid AlCl3 and to their explanation.
Synthesis of potential chemotherapeutics in bile duct infections (II)
Authors: van Kampen E. J.
Published: September 2010

In a previous publication1) the synthesis was described of 3′,3″‐disulphanilylamino‐phenolphthalein as a potential chemotherapeutic for combating infected bile ducts.

Below the synthesis is described of mono‐sulphanilylamido‐phenolphthalein, α‐phenyl‐β‐(3‐sulphanilylamido‐4‐hydroxyphenyl)‐propionic acid, and 2‐carboxy‐3′‐sulphanilylamido‐4′‐hydroxybenzophenone. An investigation for informative purposes of the latter two compounds has been made as regards their bacteriological and pharmacological properties.
Über das Verhalten einiger α,α′‐Iminosäuren als Substratkomponenten in biologischen Systemen: Untersuchungen in Beziehung zu Eiweissproblemen. II
Authors: Kögl F. , de Flines J.
Published: September 2010

Zur Prüfung der Frage ob α,α′‐Iminosäuren im Sinne der Hypothese von Karrer als Zwischenprodukte bei der enzymatischen Transaminierung eine Rolle spielen, wurde ein mit C14, D und N15 markiertes Präparat von L‐α‐L‐α′‐Imino‐propionsäure‐glutarsäure neben α‐Ketoglutarsäure und Alanin zu einem Homogenat von Rattenmuskel gefügt. Die nach der enzymatischen Umsetzung isolierte L‐Glutaminsäure war nicht radioaktiv, was im Prinzip gegen eine intermediäre Rolle der α,α′‐Iminosäure spricht. Die gebildete L‐Glutaminsäure zeigte jedoch eine geringfügige Erhöhung der N15‐Konzentration. Ein Erklärungsversuch hierfür wird diskutiert.

Weiterhin wurde untersucht, ob die verschiedenen Stereoisomeren von α,α′‐Imino‐propionsäure‐bernsteinsäure und von α,α′‐Imino‐propionsäure‐glutarsäure imstande sind, Alanin und Asparaginsäure bzw. Glutaminsäure als Substratkomponenten von Leuconostoc dextranicum, Leuconostoc mesenteroïdes P60 oder Lactobacillus arabinosus zu ersetzen. Dies war nicht der Fall.
Biphenyl derivatives III: Basic esters of biphenyl‐2‐carboxylic acid and a number of its partially or totally hydrogenated analogues
Authors: Veer W. L. C. , Oud P. J. A.
Published: September 2010

The synthesis of the hitherto unknown 2‐phenyl‐cyclohexene‐l‐carboxylic acid and 2‐cyclohexyl‐cyclohexene(1 or 6)‐carboxylic acid is described. These acids, as well as 2‐phenylbenzoic acid, trans‐2‐phenyl‐cyclohexane carboxylic acid, 2‐cyclohexyl benzoic acid, 2‐cyclohexyl‐cyclohexane carboxylic acid and biphenyl‐2‐acetic acid were converted into their tertiary aminoalkyl esters. These esters exhibit various pharmacological properties, the antispasmodic activity being most pronounced. In this respect (2‐dimethylaminoethyl)‐2‐phenyl‐cyclohexene‐l‐carboxylate and (2‐diethylaminoethyl)‐trans‐2‐phenyl‐cyclohexane carboxylate are the most powerful compounds of the series.
Cis‐ and trans‐quinonedichloride
Authors: ter Borg A. P.
Published: September 2010

Contrary to the results of earlier investigators it is found that the reaction of chlorine with quinone is a cis‐addition. Conditions are studied for the conversion of cis‐quinonedichloride into the trans‐isomer and subsequently into 2,3‐dichloroquinol.

The course of the reaction between sulphuryl chloride and quinol is elucidated.
The dipole moments of 2,2′‐dipyridyl and of 4,4′‐dipyridyl
Authors: Goethals C. A. , Wibaut J. P.
Published: September 2010

In a paper entitled “The configuration of 2,2′Dipyridil” Fielding and Le Fèvre) point out some errors occurring in a publication) by one of the present authors (G), entitled: “Electric Moments of Pyridine Derivatives”. These errors, which the British authors kindly consider to be “probably clerical errors”, are very annoying, so that we think it useful to correct them as yet.
The behaviour of 1,3,5‐trinitrobenzene in alkaline solution
Authors: Ketelaar J. A. A. , Bier A. , Vlaar H. T.
Published: September 2010

No exchange was observed when sym. trinitrobenzene was dissolved in a solution of NaOH containing heavy water.
The separation and identification of normal aliphatic aldehydes and methyl ketones
Authors: Kramer P. J. G. , van Duin H.
Published: September 2010

n‐Aliphatic aldehydes and n‐methyl ketones up to and including C18 are separated by partition chromatography of the 2,4‐dinitrophenylhydrazones on silica‐gel with light petroleum as mobile and nitromethane as immobile phase. Identification is possible by means of the retention volumes.
The separation and identification of normal aliphatic alcohols
Authors: van Duin H.
Published: September 2010

With the aid of 4‐dialkylamino‐3,5‐dinitrobenzoyl chloride primary normal aliphatic alcohols and normal methyl‐carbinols up to ca. C14 are practically quantitatively converted into coloured esters, which can be separated by partition chromatography. Identification is possible by means of the retention volumes, while a quantitative determination can be made by measuring the UV absorption.

The theory of partition chromatography is extended and it is shown that the logarithms of the true retention volumes for terms of a homologous series plotted against the number of C‐atoms must give a straight line, provided the behaviour of the solutions and chromatographic system is ideal. The slope of this line is determined exclusively by the partition system and the nature of the homologous series. The significance of this relationship for the identification of homologues is discussed.
Investigation of the alkaloids of Punica Granatum L. by partition chromatography
Authors: Wibaut J. P. , Beyerman H. C. , Enthoven P. H.
Published: September 2010

In recent literature doubts are expressed about the accepted structure of the anthelmintic substance pelletierine, one of the four alkaloids said to occur in the bark of the pomegranate tree (Punica granatum L.) It has been suggested that the “pelletierine” of the literature is in reality isopelletierine, which would reduce the number of alkaloidal components to three.

The present investigation reports on the analyses by means of partition chromatography on paper of two samples of commercial “pelletierine sulphate” and of an extract made of pomegranate bark. Four (or five) spots were found, three of which had RF‐values identical with those of synthetic pseudopelletierine, d,l‐isopelletierine and d,l‐methylisopelletierine. This is a convenient way of establishing the presence of these three compounds in pharmaceutical “pelletierine” preparations and of establishing the presence of one (or two) more substances not yet identified.
Note on the preparation of 4‐aminopyridine
Authors: Wibaut J. P. , Herzberg S. , Schlatmann J.
Published: September 2010

Contrary to the opinion of several authors, 4‐aminopyridine can be obtained by the method of Koenigs and Greiner in the yield mentioned by these workers, provided an excess of alkali be added to the reaction mixture from which the 4‐aminopyridine is to be separated.
Micro‐synthesis of cyanide from barium carbonate
Authors: Sixma F. L. J. , Hendriks H. , Helle K. , Hollstein U. , van Ling R.
Published: September 2010

A new and very simple micro‐synthesis of HC14N from barium carbonate, ammonium chloride, and potassium is described. Yields of 94% ± 1.5% were obtained. Experiences with some other simple and fast methods described in the literature are reported as well.
Quelques nouvelles halogénations effectuées avec les N‐bromo‐ et N‐chlorosuccinimides
Authors: Buu‐Hoï Ng. Ph.
Published: September 2010

On décrit plusieurs nouveaux exemples d'application des N‐chloro‐ et N‐bromosuccinimide à la préparation de composés aromatiques ou hétérocycliques halogénés utiles pour la synthèse (amines aromatiques, éthers de naphtols et de polyphénols, dérivés de la pyridine, de l'indole et de la quinoléine). Il est montré que les N‐halogénoimides permettent souvent de réaliser commodément des monohalogénations dans des cas où l'halogéne libre donnerait une polyhalogénation.
Synthesis and some pharmacological properties of esters of some n‐alkyl homologues of tropinol and ψ‐tropinol: 3rd Communication on Derivatives of Tropinols
Authors: Siegmann C. M. , Wibaut J. P.
Published: September 2010

The syntheses described are those of a number of homologues of tropinone, viz. N‐ethyl‐nor‐tropinone, N‐n‐propyl‐nor‐tropinone, N‐iso‐propyl‐nor‐tropinone, and of a number of tropinols, viz. N‐ethyl‐norψ‐tropinol, N‐ethyl‐nor‐ψ‐tropinol, N‐n‐propyl‐nor‐ψ‐tropinol, and N‐isopropyl‐nor‐ψ‐tropinol. The benzoic esters of these tropinols are prepared, and also the d,l‐tropic ester of N‐ethyl‐nor‐ψ‐tropinol.

The said. benzoic esters are investigated for local anaesthetic action with the aid of the cornea reflex.

d,l‐Tropyl‐N‐ethyl‐nor‐ψ‐tropeine has neither a mydriatic nor a parasympatholytic effect.
On the theory of aromatic substitution: V. Note on the use of Hammett's equation for the correlation of rates of electrophilic and nucleophilic substitution reactions
Authors: Sixma F. L. J.
Published: September 2010

A discussion is given of the use of Hammett's equation for the correlation of the rates of electrophilic and nucleophilic substitution reactions in the benzene nucleus. The discussion is based on a simplified theory of the inductive effect of certain types of substituents given in previous papers 2)3). It is shown that according to the theory the Hammett relation should hold for those cases where the influence of the substituent on the reaction rate is determined only (or for the greater part) by this “inductive” effect. In those cases where resonance interactions play a decisive role deviations may occur.
Séparation des aminoacides par chromato‐ graphie ascendante monodimensionnelle et leur dosage par photométrie directe sur le papier
Authors: de Wael J. , Cadavieco R. Diaz
Published: September 2010

Les auteurs décrivent une méthode pour la détermination des aminoacides par photométrie directe des bandes colorées, obtenues par la chromatographie sur papier.

Les facteurs qui influencent la reproductibilité des expériences ont été étudiés.

L'analyse de deux protéines effectuée avec cette méthode donne des résultats qui correspondent aux chiffres, trouvés dans la litérature.
The polarographic reduction of conjugated hydrocarbons: IV. The mechanism of the reduction of various alternant and non‐alternant hydrocarbons
Authors: Hoijtink G. J. , van Schooten J. , de Boer E. , Aalbersberg W. Ij.
Published: September 2010

The current‐voltage curves of various alternant and non‐alternant hydrocarbons were measured in 75% and 96 % dioxane‐water. In many cases the limiting current of the first reduction wave corresponds to the overall addition of one electron. From the effect of the increase of the percentage of water and the addition of hydrogen iodide on the limiting current and on the half‐wave potential of the first and the second wave, evidence was obtained about the reduction mechanism. The primary steps of the reduction are: R + e →← R′ and R′ + e →← R″ the standard potential determined by the first electron addition is less negative than that of the second step.

When the rate of proton addition to R′ is low with respect to the rate of diffusion of R′, the first wave is a one‐electron wave and the second wave involves the reduction to R″. When R′ reacts with a proton in the electrode surface layer, the reduction proceeds according to:

magnified image

The reduction mechanism is discussed in detail and compared with the experimental results reported in this paper or found by other investigators.
Studies on vitamin D, I. the synthesis of vitamin D3 3 C14
Authors: Havinga E. , Bots J. P. L.
Published: September 2010

The synthesis of vitamin D3 3 C14 is described. Special attention has been paid to the technique of the photochemical conversion of 7‐dehydro‐cholesterol 3C14 (small quantities) and to the isolation of the labelled vitamin D3 from the irradiation mixture. Some biological experiments are briefly communicated.
Aconic acid and related compounds: II. The reaction of aconic acid with diazomethane
Authors: Rekker R. F. , Brombacher J. P. , Nauta W. Th.
Published: September 2010

From aconic acid with an excess of diazomethane a nitrogen‐containing compound is formed. The structure was established to be methyl 3,4‐(4′,5′‐Δ1‐pyrazolino) aconate. Heating of this compound resulted in the splitting off of a molecule of nitrogen and the formation of a methyl‐substituted aconic acid ester hitherto unknown in the literature.
Phosphatidic acids and derivatives: V) Synthesis of bisglycol‐phosphatidic acids, starting from monoacylglycols
Authors: van Gijzen J. , Verkade P. E.
Published: September 2010

The preparation and some properties of three bisglycol‐phosphatidic acids, containing stearic, palmitic or myristic acid as component acid, are described.
Naphthodioxan (2,3‐dihydro‐naphtho‐[2,3]‐p‐dioxin), some derivatives and azo dyes. I
Authors: Heertjes P. M. , Ter Horst A. M. , Persijn J. M.
Published: September 2010

The preparation and orientation of naphthodioxan (2,3‐naphtho‐p‐dioxan (2,3‐dihydro‐naphtho‐[2,3]‐p‐dioxin)), 5‐, 6‐, and 7‐mononitro‐naphthodioxan, 5‐, 6‐, 7‐monoacetylamino‐naphthodioxan, as well as 5‐, 6‐, and 7‐naphthodioxan monosulphonic acid and some derivatives, are described in this paper.
The non‐existence of sesquiammonium phosphate
Authors: Ketelaar J. A. A. , Rundervoort H. J. , Lobatto J. L. , Hooge F. N.
Published: September 2010

It follows from measurements of the NH3‐pressures of preparations of ammonium phosphate with a composition intermediate between mono‐ and diammonium orthophosphate that no indication was obtained of the existence of a sesquiammonium orthophosphate, (NH4)3H3(PO4)2, as postulated by De Passillé. At temperatures above 135° C water is also separated off, with the formation of polyphosphates.
The concentration dependence of the electrophoretic mobility of soap micelles
Authors: Stigter D.
Published: September 2010

The dependence on the soap concentration of the micellar mobility is explained primarily by a solvent backflow. The observed limiting slope is corrected for the change of the true micelle mobility which is due to the variation of the effective ionic strength with the soap concentration. The corrected slope is interpreted in terms of a volume of solvent entrained by 1 gram of micellar soap. An approximate calculation confirms the experimental finding that the amount of entrained solvent becomes larger when the ionic strength of the solution decreases.
Ozone absorption and ozonolysis of cyclooctatetraene
Authors: Wibaut J. P. , Sixma F. L. J.
Published: September 2010

At −31° cyclooctatetraene absorbs 3.5 moles of ozone. Among the products of the ozonolysis of cyclooctatetraene, ethane‐1,1,2,2‐tetracarboxylic acid and succinic acid were found. The results may be interpreted either in terms of an equilibrium between cyclooctatetraene and bicyclo‐(4.2.0)‐octatriene or in terms of a reaction mechanism analogous to the one postulated by Friess and Boekelheide for halogen addition.
Steric effects on mesomerism: XIII. Preparation of 2,6‐dimethyl‐4‐nitroaniline
Authors: Wepster B. M.
Published: September 2010

Nitration of 2,6‐dimethyl‐(p‐toluenesulpho) anilide or 2,6‐dimethyl‐benzenesulphoanilide in aqueous acetic acid, followed by deacylation, gives 2,6‐dimethyl‐4‐nitroaniline in yields of 80‐90%. These and other procedures are discussed.

The rate of deacylation of 2,6‐dimethyl‐4‐nitroacetanilide in sodium methoxide solution is in agreement with the considerable steric inhibition of mesomerism to be expected.
Preparation and constitution of some benzene derivatives containing the acetylamino and the methylsulphonyl group as substituents
Authors: Bolssens J. , Brouwers J. A. C. Th. , Choufoer J. H. , Kats A. , Verkade P. E. , Wepster B. M.
Published: September 2010

The preparation of a number of benzene derivatives containing the acetylamino and the methylsulphonyl group as substituents is described. Proofs for the constitution of the compounds obtained are furnished.
Glycerol‐α‐ and β‐monoiodohydrin
Authors: Hessel L. W. , van Lohuizen O. E. , Verkade P. E.
Published: September 2010

For the glycerol‐monoiodohydrins of m.p. 48‐49° and 53.5‐54.5° new methods of preparation are described. The last‐mentioned compound has thus become reasonably accessible for the first time. The statements in the literature as to the constitution of the first‐mentioned compound are discussed. Unambiguous evidence for the constitution of the two compounds is furnished: the compound of m.p. 48‐49° is the α‐isomer, that of m.p. 53.5‐54.5° the β‐isomer.
Studies in the use of the manganese dioxide electrode in acid ‐ Base titrations
Authors: Issa I. M. , Sadek E. A.
Published: September 2010

Manganese dioxide, prepared by electro‐deposition on a platinum substrate from a manganous salt solution, proved to be a suitable electrode combination for detecting the end point in neutralization reactions.
The preparation of tetra‐t‐butoxysilane
Authors: Breederveld H. , Waterman H. I.
Published: September 2010

Tetra‐t‐butoxysilane has been prepared from tri‐t‐butoxybromosilane and sodium‐t‐butoxide.
The influence of oestrogens on the protein and lipid metabolism of the mouse uterus, studied with acetate‐1‐C14
Authors: Emmelot P. , Bosch L.
Published: September 2010

The in vitro incorporation of tracer from acetate‐1‐C14 into proteins, cholesterol, and fatty acids of isolated uterine segments was estimated 20 hours after an in vivo treatment of ovariectomized mice with 0.1 μg oestrone, 17β‐oestradiol or oestriol.

The hormone‐treated animals showed a significantly higher incorporation of C14 than the untreated groups.

In general the following order of activity was noted: 17β‐oestradiol> oestrone oestriol.
The heats of combustion, formation and isomerization of propanethiol‐1, propane‐thiol‐2 and 2‐thiabutane
Authors: Hubbard Ward N. , Waddington Guy
Published: September 2010

By use of a rotating bomb calorimeter the isothermal energy change (‐ΔUc°) at 25 °C of the reaction C3H8S(l) + 13/2 O2(g) + 52H2O(l) → 3CO2 + H2SO4.55H2O(l) has been measured for propanethiol‐1 (I), propanethiol‐2 (II), and 2‐thiabutane (III). The combustion results, supplemented by vapor pressure, heat of vaporization and gas imperfection data, gave values (in kcal.mole−1) of the standard heats of formation at 25° C of each of the three C3H8S compounds, in the liquid and ideal gaseous states, as follows: I(l), ‐23.69 ± 0.16; I(g), ‐16.04 ±0.16; II(l), ‐25.12 ± 0.15; II(g), ‐18.04 ± 0.16; III(l), ‐21.71 ± 0.27; III(g), ‐14.07 ± 0.27. The reliability of the derived heats of isomerization is discussed.
The rate of condensation of some tripeptide methyl esters in solution
Authors: Sluyterman L. A. Ae. , Veenendaal H. J.
Published: September 2010

The condensation rate of a few tripeptide methyl esters in methanol has been studied at 65° C. The peptide esters with a glycyl residue at both ends have been found to be equally reactive, regardless of the nature of the amino acid residue in the middle. A side chain situated on one of the terminal amino acid residues decreases the reaction rate (table I).
Volumetric determination of uranium in poor ores
Authors: Smit W. M. , Klinkhamer J.
Published: September 2010

The conditions necessary to prevent interference of Fe with the oxidimetric titration of U have been derived on the basis of calculations regarding the relations between the redox potential and the pH. The method of calculation may be applied to other possibly interfering ions. It is shown that a successful determination of both U and Fe can be carried out in a solution with an atomic ratio Fe/U of 1000 and containing only 2 mg of U per 150 ml. By using the “dead stop end point” indication method, U and Fe may be determined separately without previous separation and without any pretreatment but reduction by a common Jones reductor.
The chlorination of 4‐amino‐2‐hydroxy‐benzoic acid
Authors: v. d. Stelt C. , Suurmond B. G. , Nauta W. Th.
Published: September 2010

In an attempt to prepare 4‐amino‐3,5‐dichloro‐2‐hydroxy‐benzoic acid (I) from 4‐amino‐2‐hydroxy‐benzoic acid (II) by a chlorination reaction, it was found that the isolated reaction product was identical with 2,4,4,6,6‐pentachloro‐cyclohexene‐1‐dione‐3,5 (III). Exhaustive chlorination of 2,4‐dihydroxy‐benzoic acid (IV) led to the same 1,3‐dihydroxy‐benzene derivative. (I) could be prepared by chlorination of 4‐acetylamino‐2‐hydroxy‐benzoic acid (V) to 4‐acetylamino‐3,5‐dichloro‐2‐hydroxy‐benzoic acid (VI) and subsequent saponification of the latter compound. By converting I into 3,5‐dichloro‐2‐hydroxy‐benzoic acid (VII) and into 3,5‐dichloro‐2,4‐dihydroxy‐benzoic acid (VIII), the 3,5‐position of the chlorine atoms in I and VIII could be proved.
Naphthodioxan, some derivatives and azo dyes: II
Authors: Heertjes P. M. , Ter Horst A. M. , Persijn J. M.
Published: September 2010

Some derivatives of naphthodioxan, 5‐amino‐naphthodioxan, and of naphthodioxan‐7‐sulphonic acid, including azo dyes, mostly substituted in the 5‐ and 10‐positions, are described in this paper.
Chemistry of acetylenic ethers X. Note on the use of ethoxy‐acetylene for the preparation of acid anhydrides
Authors: Arens J. F. , Doornbos T.
Published: September 2010

Some years ago it was found that ethoxy‐acetylene (ethoxy‐ethine) is a very mild reagent for the preparation of carboxylic anhydrides.

Afterwards we observed that also non‐carboxylic acids are transformed into their anhydrides by this reagent.

2 RCOOH + HC ≡ C‐OC2H5 → (RCO)2O + CH3COOC2H5

2 RSO3H + HC ≡ C‐OC2H5 → (RSO2)2O + CH3COOC2H5

From a recent paper by E. R. H. Jones and co‐workers 2) it appears that these investigators examined the same reactions. Experiments with several mono‐ and dibasic carboxylic acids and with a sulphonic acid are recorded. In addition to these examples we give below a description of the use of ethoxy‐acetylene for the preparation of tetraethyl pyrophosphate from diethyl phosphate.
The solubility of bilirubin
Authors: Overbeek J. Th. G. , Vink C. L. J. , Deenstra H.
Published: September 2010

The titration curve of a suspension of bilirubin with NaOH has been determined and analysed. A value of 5 × 10−11 mole/l for the solubility of undissociated bilirubin has been derived from the titration.
On the reaction of cinnamyl alcohol with formaldehyde
Authors: Beets M. G. J. , van Essen H.
Published: September 2010

The acid‐catalyzed reaction of cinnamyl alcohol with formaldehyde has been studied. From the complex reaction product two m‐dioxane derivatives and a triol have been isolated, and their structures have been studied.
On the rate of oxidation of di‐alkylsulphoxides in monolayers
Authors: Blokker P. C. , Paar E.
Published: September 2010

In order to obtain more information on the conditions under which the reactivity of substances in a liquid/air interface is affected, the oxidation of di‐alkylsulphoxides in monolayers by very dilute potassium permanganate solutions was studied.

In a few cases with expanded films, where the energy of activation could be calculated, this energy was low. With increasing packing density of the molecules in the film the pseudo‐unimolecular reaction constant increased; this is probably caused by an increase in the entropy of activation.
The action of diazoacetic ester on pyridone‐2: A new synthesis of 2‐pyridoxyacetic acid
Authors: Maas J. , de Graaff G. B. R. , den Hertog H. J.
Published: September 2010

Ethyl 2‐pyridoxyacetate is obtained as chief product, together with a small amount of N‐(2‐pyridonyl) acetic ester, by reacting pyridone‐2 with ethyl diazoacetate.
Synthèse du 1,1,2,2‐tétradeutérioacénaphtène et du 9,9‐dideutériofluorène
Authors: Buu‐hoï Ng. Ph. , Eckert B. , Jacquignon P.
Published: September 2010

On décrit la préparation, à partir de l'acénaphtènequinone et de l'oxyde de deutérium, du 1,1,2,2‐tétradeutérioacénaphtène par la méthode de Clemmensen; Iorsque la réduction est incomplète, on aboutit au 1‐oxo‐2,2‐dideutérioacénaphtène. Une réduction analogue de la fluorénone conduit au 9,9‐dideutériofluorène.
Carbamates. II. Reactions‐ of 2,4 di‐isocyanato‐toluene
Authors: Gaylord Norman G. , O'Brien John J.
Published: September 2010

The dicarbamates prepared by the reaction of various monofunctional alcohols and phenols with 2,4‐diisocyanatotoluene are well‐defined solids which are useful in the characterization of these hydroxy compounds.
Untersuchungen über Derivate von 2,3‐Dihydro‐pyran‐2,4‐dion: (2. Mitteilung)
Authors: Kögl F. , Salemink C. A.
Published: September 2010

In Fortführung unserer Untersuchungen über die antibakterielle Wirkung von homologen Dehydracetsäuren mit normalen Seitenketten wurden in der vorliegenden Arbeit auf analoge Weise Derivate mit verzweigten Seitenketten dargestellt. Im allgemeinen zeigen diese Derivate bei verschiedenen Bakterienarten eine gesteigerte Hemmwirkung.
The ozonolysis of quinoline, 6,7‐dimethylquinoline, 5,8‐dimethylquinoline, and 2,3‐dimethylquinoline in connection with the reactivity of the bonds in the ring system
Authors: Wibaut J. P. , Boer H.
Published: September 2010

When ozone acts on quinoline and on some dimethylquinolines, the main reaction consists in an attack on the benzene ring, via a 5,6‐7,8‐diozonide; this follows from the products obtained after ozonolysis. The 5,10‐, 6,7‐, and 8,9‐bonds are not affected by ozone.

The reactivity of the ring system of quinoline towards ozone therefore greatly resembles the reactivity of the ring system of naphthalene towards the same reagent. The 5,6‐ and 7,8‐bonds in the quinoline ring system behave in the same manner towards ozone as do the α,β‐bonds in the ring system of naphthalene.

Upon the ozonolysis of 2,3‐dimethylquinoline, besides glyoxal there is also formed dimethylglyoxal; this points to the fact that by the side of the main reaction a side reaction takes place, in which the pyridine ring is attacked through addition of a molecule of ozone to the 3,4‐bond.
The dynamic state of the thyroid gland in cases of hypertension diagnosed by means of radioactive iodine
Authors: Fateeva M. N.
Published: September 2010

In cases of hypertension, the absorption of I131 by the thyroid gland can be determined by direct measurement.

More than 60% of the patients exhibit a hyperfunction of the thyroid gland in the first stage of hypertension, while the gland's function is reduced in two‐thirds of the cases during the third stage.
Local measurement of I131 uptake in the thyroid gland
Authors: Jaspers A. M. J. , Marcuse H. R.
Published: September 2010

Based on a new development of Geiger‐Müller tubes, a collar‐shaped device is described, which can be applied round the patient's neck in order to measure directly the uptake of I131 in the thyroid gland. Methods are indicated for calibrating and for measuring the corrections due to the background and the activity in the blood.
The I131 thigh neck clearance test in relation to drug administration
Authors: Maclagan N. F. , Meade B. W.
Published: September 2010

500 patients have been examined by the I131 thigh neck clearance test, and the results correlated with clinical data and estimations of basal metabolic rate. The test consists in the oral administration of 30 μc of I131, followed by alternate neck and thigh counts under defined conditions over the following one to two hours. The clearance represents the ratio of the rise in neck counts over a 60 minute period divided by the mean thigh count taken at the same time, and gives normal figures of from 1 to 9.

In untreated patients there is good correlation in the B.M.R., but as with other radioactive tests of thyroid function, discrepancies occur after various forms of medical treatment. A. number of goitrogens and blocking agents were tested for their ability to limit the retention of I311 by the thyroid if given at the conclusion of the test. Of these potassium iodide gave the best results but is not recommended for routine use.
The influence of prominal on the thyroid function of the rat
Authors: Schwarz F.
Published: September 2010

The experiments show the rather surprising fact that prominal does not depress, but enhance the I131 uptake of the thyroid gland. The radioactivity of the gland was determined by in vitro measurements.

Further we used an apparatus constructed in our laboratory for the determination of thyroid activity in the living rat.

The results obtained in this way are discussed.
Oxydation phosphorylante et carence en thiamine
Authors: Frei J. , Wermuth R.‐M.
Published: September 2010

Nous avons étudié dans le présent travail l'oxydation phosphorylante dans des homogénéisats de foies de rats normaux et carancés en thiamine. La formation de triphosphate d'adénosine a été déterminée par la mesure sur chromatogrammes sur papier de l'incorporation de phosphate radioactif dans le phosphate labile. Nous obtenons un abaissement significatif de la phosphorylaton de l'A.D.P. dans l'homogénéisat de foies de rats carencés en vitamine B1 pendant l'oxydation du citrate et du succinate. La consommation d'oxygène est diminuée également, mais elle n'est pas significative pendant les 15 prèmieres minutes des expériences. Nos recherches se poursuivent pour voir si nous avons affaire à une lésion au niveau des mitochondries provoquant le départ de facteurs indispensables.
The determination of calcium in biological fluids by flame spectrophotometry
Authors: Macintyre I.
Published: September 2010

The direct flame photometric determination of calcium in serum and urine is described. Means of overcoming interferences are detailed. A. study of the Kramer‐Tisdall procedure underestimates the calcium content.
Gas analysis by thermal conductivity measurement
Authors: Visser B. F.
Published: September 2010

Thermal conductivity measurement (also known as diaferometry or katharometry) is a non‐specific, physical gas analysis method.
Beiträge zur Methodik der fluorometrischen Porphyrinbestimmung
Authors: Weber K. , Valić F.
Published: September 2010

Es wird die fluorometrische Apparatur, besonders hinsichtlich ihre Verwendung für Porphyrinbestimmungen kritisch besprochen. Auf günstige Lichtquellen und einwandfreie Filterkombinationen wird hingewiesen. Es werden Lösungen und Adsorbate von Rhodamin B an Filterpapier als Ersatz für Standarde von Koproporphyrin bei der fluorometrischen Analyse empfohlen und diesbezügliche Eichkurven und Umrechnungstabellen mitgeteilt.
Eine Apparatur zur Hochspannungs‐Papierelektrophorese
Authors: Werner G.
Published: September 2010

Es wird eine Apparatur beschrieben, mit der die Papierelektrophorese bei Spannungen bis 10 000 Volt und Wanderungswegen bis 1 Meter möglich ist. Eine besondere Art des Aufbringens der Substanzlösung auf den Papierstreifen wird beschrieben, sowie über eine Einrichtung berichtet, mit welcher es möglich ist, besonders lange Papierstreifen gleichmässig und reproduzierbar anzufeuchten. Die Leistungsfähigkeit wird an Trennungen von Aminosäuren, Peptiden, Zuckern und anorganischen Salzen gezeigt.
The determination of the higher saturated fatty acids in blood serum
Authors: Pikaar N. A.
Published: September 2010

A description is given of the determination of the higher even‐numbered, straight‐chain saturated fatty acids in small amounts of blood serum.
The detection of thyroxine and related compounds on paper chromatograms by optical methods
Authors: Maclagan N. F. , Bowden C. H. , Wilkinson J. H.
Published: September 2010

The ceric sulphate‐arsenious acid reagent has been applied to the detection of thyroxine and triiodothyronine on paper chromatograms. The sensitivities achieved were such as to suggest that this reagent might enable physiological concentrations of these substances to be detected. Preliminary experiments on the extraction of the iodine components of plasma are described.
Die Bedeutung routinemässiger Phosphatasebestimmungen in Klinischen Labors: Eine neue, einfache Standard‐Methode
Authors: Raabe Siegfried
Published: September 2010

Einer routinemässigen Anwendung der meisten bisherigen Methoden stand entgegen, dass sie zu umständlich, z. T. auch mit biochemischen Fehlermöglichkeiten behaftet sind. Deshalb entwickelten wir eine Standard‐Methode, die exakte Werte liefert und trotzdem technisch so einfach ist, dass sie auch in einfach eingerichteten Labors bequem und in grossen Reihen ausgeführt werden kann. Routinemäszige Phosphatase‐Bestimmungen erlauben dem Laborleiter wertvolle Hinweise für den Kliniker; sie sollten daher mehr Eingang in den klinischen Labors finden.
Über die Veränderungen der Kohlenhydrathaltigen Serumproteine bei manchen allergischen Erkrankungen
Authors: Bodur Hatice
Published: September 2010

Bei 43 Fällen von verschiedenen allergischen Erkrankungen wurde der Gehalt von proteingebundenen Hexosen im Serum, sowie deren Verteilung auf die Albumin‐ und Globulinfraktion untersucht. Je nach dem Verlauf der Erkrankung konnten wir unsere Fälle in 2 Gruppen einteilen: in manifest verlaufende allergische Fälle, die eine Vermehrung des Hexosegehalts in der Globulinfraktion aufwiesen und in Fälle mit latentem Krankheitsverlauf, bei denen eine Verminderung der Hexosemengen in der Albuminfraktion festzustellen war.
Raman spectra of aliphatic chlorine compounds: I. Chloroethanes and chloropropanes
Authors: Gerding H. , Haring H. G.
Published: September 2010

In the present paper, No. I of a series comprising a comparative study of the Raman spectra of a great number of different kinds of aliphatic chlorine compounds, chloroethanes and chloropropanes are considered.

Thirteen chloropropanes have been prepared and their Raman spectra determined. For twenty‐six of the twenty‐nine possible derivatives, frequency data therefore are now available. Quantitative polarization measurements have been carried out for the thirteen compounds and for six other chloropropanes for which only frequencies had been published.

For the chloroethanes, chloropropanes, and a number of chlorobutanes. “specific group frequencies” have been inferred for the following groups: CH3CH2Cl, CHCl, CHCl2, CH2, and CCl3. The constancy of these characteristic frequencies is retained in compounds containing more of these groups, either similar or different.

The influence which the degree of substitution of chlorine for hydrogen exerts on the numerical value of a specific group frequency gives indications as to the number of chlorine atoms present in the rest of the molecule. Regularities have been observed in the trend of the carbon‐carbon chain and carbon‐chlorine vibrational frequencies with the degree of substitution.

No distinct indications of the presence of rotational isomerism in the compounds studied have been found.
Polymerization of ortho‐methoxy‐allyl benzene. Dimerization combined with hydration
Authors: van der Zanden J. M. , de Vries G.
Published: September 2010

For a hydrated dimer of ortho‐methoxy‐allyl benzene a description is given of the preparation and isolation, and of the manner in which we established the structure by decomposition and synthesis. The Experimental Part is followed by an enumeration of the compounds obtained during our investigation in so far as they are not mentioned in the literature.
The chemistry of acetylenic ethers XIV: The reaction of ethoxyacetylene with hydrazoic acid
Authors: Sinnema Y. A. , Arens J. F.
Published: September 2010

Ethoxyacetylene I reacts easily with hydrazoic acid to yield 1,1‐diazido‐1‐ethoxy‐ethane II. The structure of this compound appears from the fact that aniline converts it into 1‐phenyl‐5‐methyltetrazole, whereas the action of ethanol or of sodium ethoxide leads to the formation of ethyl‐orthoacetate.
On the kinetics of the oxidation of phloroglucinol
Authors: Stein H. N. , Tendeloo H. J. C.
Published: September 2010

Kinetic experiments indicate that the first step of the oxidation of phloroglucinol by Fe (CN)6 − − − is reversible. The equilibrium concerned, however, is not stable, since one of the species participating, i.e. the first oxidation product of phloroglucinol, is broken down irreversibly. Some data are given about the reaction rates concerned, and the existence of a free radical as an experimentally accessible substance is established.
Raman spectra of aliphatic chlorine compounds: III. Chloropentenes and chloropentadienes
Authors: Gerding H. , Haring H. G.
Published: September 2010

The Raman spectra are reported for the chloropentenes CHClCl. CHCl, CHCl. CHCl2 CHClCCl. CHCl. CHCl. CCl3, CCl2CCl. CHCl. CHCl. CHCl2, and CCl2CCl. CHCl. CHCl. CCl3 and for the chloropentadienes CHClCCl. CHCl. CClCHCl, CCl2  CCl. CHCl. CCl  CHCl, CHClCCl. CHCCl. CCl3, CCl2CCl, CHCCl. CCl3 and CCl2CCl. CClCCl.CCl3.

A comparative study is made between these spectra, as well as those previously investigated by Gerding and Rijnders, and the spectra of chloropropanes and chloropropenes. The carbon‐carbon double‐bond frequency decreases with increasing substitution of chlorine for hydrogen in the single‐unsaturated compounds, just as in the chloropropenes. For the double‐unsaturated compounds a characteristic pattern of (C  C) Raman lines appears if the double bonds are conjugated, which allows of conclusions being drawn for a few compounds with regard to their structural formulae.

Characteristic hydrogen frequencies deduced for CHCl2, CHCl, and  CHCl groups in these chlorohydrocarbons show values which for a number of compounds deviate from the “specific group frequencies” derived from the spectra of propanes and propenes.

The evidence for the strong Raman line at about 400 cm−1 as characterizing a CCl3 group or the configuration magnified image, is considerably strengthened. Its frequency value increases with increasing mass MX.
The chemistry of acetylenic ethers XV: The reaction of ethoxyacetylene with aqueous solutions of tertiary aliphatic amines
Authors: Arens J. F. , Bouman J. G. , Koerts D. H.
Published: September 2010

Ethoxyacetylene I reacts with tertiary aliphatic amines and water to yield (α‐ethoxyvinyl)‐trialkylammonium hydroxides II. Several crystalline salts of these bases were obtained. Catalytic hydrogenation of (α‐ethoxyvinyl)‐trimethylammonium iodide IIa yielded trimethylammonium iodide and diethyl ether.
Conversions of (3‐pyridyl)‐methanal
Authors: Wibaut J. P. , Wallingford H. P. , Rang H. J. , Kettenes D. K.
Published: September 2010

The reactions are described of (3‐pyridyl)‐methanal with acetic anhydride (formation of (3‐pyridyl)‐acrylic acid), with hippuric acid (synthesis of β‐(3‐pyridyl)‐alanine), with phenyl‐magnesium bromide (synthesis of (3‐pyridyl)‐phenyl‐carbinol), with the iodomethylate of α‐picoline, and with dimedone. (3‐pyridyl)‐methanal does give the Cannizzaro reaction, but not the pyridoin condensation.
The cleavage of some mixed aliphatic‐aromatic tin compounds by silver nitrate
Authors: Lesbre M. , Buisson S. R. , Luijten J. G. A. , van der Kerk G. J. M.
Published: September 2010

A quantitative study was made of the reaction between triethylphenyltin, diethyldiphenyltin, ethyltriphenyltin, and the corresponding n‐propyl‐phenyl compounds and silver nitrate in absolute ethanol at 25° C. The behaviour of the trialkyl and dialkyl compounds was markedly different from that of the monoalkyl compounds. In a tentative explanation the inductive (+ I) effect of the alkyl groups is held responsible for this phenomenon.