bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation into the type of particles occurring in concentrated solutions of 2‐1 electrolytes, in connection with the hydration of the ions
Authors: van Ruyven B. H. 
Published: September 2010

AbstractThis investigation is carried out on the basis developed for the 1‐1 electrolytes1).With the aid of Raoult's law and the theory of Arrhenius the procedure for the calculation of the degrees of ionization is described when the three free ions together bind a H2O particles. The relation thus found is adapted for the elaboration of Tammann's data at 100°.With the aid of the sulphates of positive ions the hydrations of which have been found for the 1‐1 electrolytes, the hydration of the SO4″ ion is calculated, upon which with H2SO4 solutions the hydration of the H* ion is found. This is verified with the aid of the acid sulphates having the positive ions already mentioned.The equilibrium between the hydrated ions and the ion triplets is found to be determined by αpa2. Nω/(1‐αpa) = K*, where * indicates that for the constant K, a has been taken into account.The hydrations of a number of bivalent negative ions are calculated. The hydration of the H* ion is dealt with more in detail.
Syntheses of polychloro compounds with aluminium chloride. XIV: The condensation of chloral with 1,2‐dichloroethene
Authors: Prins H. J. , Haring H. G. 
Published: September 2010

AbstractThis paper describes the compounds obtained by the condensation of chloral with 1,2‐dichloroethene (1,1,3,4,4‐pentachlorobutanone‐2; 1,2,4,4‐tetrachlorobuten‐1‐one‐3; 1,4,4,4‐tetrachlorobuten‐1‐one‐3; α,β,γ,γ‐tetrachloro‐n‐butyryl chloride), some derivatives, and the various reactions used to establish their structure.Decomposition (by the action of aluminium chloride) of 1,1,1,3,4,4‐hexachloro‐2‐methoxybutane, obtained by the condensation of α,β,β,β‐tetrachloroethyl methyl ether with 1,2‐dichloroethene, yielded the same compounds, but in other proportions. An indication of the presence of these compounds was obtained by Raman analysis.The mechanism of these reactions is briefly discussed.
α‐Substituted methylsulphonylacetonitriles: (Properties of the sulphonyl group XLII)
Authors: Dijkstra R. , Backer H. J. 
Published: September 2010

AbstractA description is given of the preparation of substituted methylsulphonylacetonitriles CH3SO2CHXCN, X being CH3SO2, CO2C2H5, C6H5SO2, CH3SO or CN.
Δ5‐steroids and provitamins D with branched side chains, III. Preparation and reduction of some Δ5‐steroid‐ω‐amides
Authors: Louw D. F. , Strating J. , Backer H. J. 
Published: September 2010

AbstractThis paper deals with the dimethyl and diethyl amides of Δ5‐cholenic acid and Δ5‐bisnorcholenic acid. These amides could be converted into the corresponding unsaturated tertiary amines by reduction with LiAlH4.
Dipole moments and structures of dihalogenocyclohexanes
Authors: Kwestroo W. , Meijer F. A. , Havinga E. 
Published: September 2010

AbstractFifteen dihalogenocyclohexanes were synthesized, and their structure was investigated by means of dipole moment measurements. The measurements were carried out in solutions in benzene as well as in carbon tetrachloride at 30°. The results show that it is almost exclusively the chair conformations which coexist in the equilibrium, the flexible form not being present in any perceptible amount.The trans‐1,4‐dihalogenocyclohexanes, where the results confirmed the assumption of μ = 0, form the simplest case. Since most conformations of the flexible form (with the exception of the so‐called stretched form) would show an appreciable moment, it seems improbable that they should be present to any important degree.For the cis‐1,4‐, the cis‐1,2‐ and the 1,1‐dihalogenides exactly the same values of the dipole moments were found in the two solvents used. Since for these compounds the two chair conformations are either identical or mirror images, the constancy of the dipole moment in different solvents again supports the view expressed above. The presence of variable amounts of the flexible form in the equilibrium would result in a change of the value of the mean dipole moment upon varying the medium.For the three trans‐1,2 compounds investigated, the dipole moments found proved to be dependent on the solvent used, the values being considerably lower in carbon tetrachloride than in benzene solutions. Significantly enough, it is precisely in these cases that the two possible chair conformations have widely different moments, the values for the la2a conformation being very low and the values for the le2e structures being around 3 D. Here the reality of an equilibrium between the two chair conformations thus becomes evident.The values obtained for the dihalogenocyclohexanes could also be understood quantitatively on the basis of the assumption of the predominance of the chair conformations in the equilibrium. In order to calculate the moments by vector addition of partial moments (i.e. the values for cyclohexyl monohalogenides), corrections have to be applied, which are slightly different from those suitable for the aliphatic polyhalogenides.Finally a short discussion is given on the problem of choosing a method of calculating “dipole moments” from data obtained with solutions, which is to combine simplicity with applicability to the study of molecular structure. A comparison of the Halverstadt‐Kumler method and that of Böttcher‐Scholte is made in the case of 1,1‐dichlorocyclohexane.
The structure of selenium tetrachloride in the solid and of tellurium tetrachloride in the liquid and the solid state
Authors: Gerding H. , Houtgraaf H. 
Published: September 2010

AbstractRaman spectra were obtained for SeCl4 in the solid and for TeCl4 in the solid and the liquid state. Polarization measurements were performed for the stronger Raman lines of liquid TeCl4. The four stronger Raman lines of SeCl4 are very close in frequency to those of pyramidal AsCl3; there is also a close analogy between the frequencies of the stronger Raman lines of TeCl4 (both in the solid and in the liquid state) and those of antimony trichloride. These findings favour the assumption that solid SeCl4 and TeCl4 have to be written as SeCl3+Cl− and TeCl2+Cl− respectively, SeCl3+ being isosteric with AsCl3 and TeCl2+ with SbCl3. Force constant and frequency calculations have been effected for the hypothetical SeCl3+ and TeCl3+ ions. The results support the above assumption.
The steady‐state temperature difference in the Hill‐Baldes technique
Authors: Iyengar B. R. Y. 
Published: September 2010

AbstractThe molal steady‐state temperature differences δ for a number of solvents have been determined by the Hill‐Baldes technique, using a precision thermistor bridge. The values of δ obtained in the present investigation as well as those available in the literature have been explained on the basis of the theory of evaporation of droplets after introducing a thermal efficiency factor, which is characteristic of the experimental method employed. The application of this technique for the determination of molecular weights in solution is also discussed.
The polarographic reduction of conjugated hydrocarbons: V. The mechanism of the reduction of various alternant and non‐alternant hydrocarbons with aromatic and olefinic double bonds
Authors: Hoijtink G. J. 
Published: September 2010

AbstractThe current‐voltage curves of various members of the series: 1‐phenyl‐n‐biphenylene polyenes, 1‐phenyl‐n‐(2,3‐benzo‐)biphenylene polyenes, 1‐n‐dibiphenylene polyenes, phenylethenes, p‐tolylethenes, o‐tolylethenes, and phenylbutadienes were measured either in 75% or 96% dioxane‐water or in both. From the results of these investigations and from the revised data of the 1‐n‐diphenyl‐polyenes it appeared that the lower members of the series of polyenes are reduced according to the mechanism inferred in paper IV. The reduction of the higher members in all probability proceeds according to the mechanism: R + e → R′ + e → R″ + H* → RH′ + H* → RH2. The various factors governing this change of the reduction mechanism are discussed.
Ultraviolet absorption spectra and configuration assigned to various substituted 9,10‐dihydroanthracenes
Authors: la Lau C. 
Published: September 2010

AbstractThe reaction of 2‐cyano‐2‐propyl radicals with several anthracenes leads to the formation of a series of interesting 9,10‐substituted 9,10‐dihydro‐anthracenes, as shown by Engelsma, Farenhorst and Kooyman1); the investigated compounds may exist in pairs of cis‐ and trans‐isomers.The present paper describes the spectrophotometric study of these compounds, which was aimed at providing a maximum of independent evidence for the structures assigned to the various derivatives.From the recorded ultraviolet absorption spectra the following conclusions have been drawn:
) purity: the parent anthracenes are absent.
) type of ring system: the investigated compounds most probably contain two “isolated” benzene rings per molecule; assuming the preservation of the original carbon‐ring system it is readily shown that the investigated compounds are 9,10‐dihydroanthracenes.
) cis/trans assignment: evidence is given for the cis or trans configuration respectively assigned to the compounds, the conclusions agree with those arrived at previously1) on the basis of stereo‐kinetical considerations.
The mutarotation and ionization of d‐glucose in alkaline solution
Authors: Los J. M. , Simpson L. B. 
Published: September 2010

AbstractThe mutarotation of d‐glucose has been studied at 0°, 15° and 25° C in unbuffered, weakly alkaline solutions by recording the change of pH with time. The dependence of the specific mutarotation velocity on the glucose concentration was extensively measured.Considering water, glucosate ions and hydroxyl ions as the only catalytically active agents, it was found that the catalytic constant of hydroxyl ions, kOH, is strongly dependent on the glucose concentration. This is the principal reason for the large discrepancy of values for kOH reported in the literature. The suggestion is made that this effect is caused by the omission of third‐order terms in the catalytic rate equation, corresponding to a concerted mechanism for the catalysis.The ionization constants of α and β d‐glucose, Kiα and Kiβ respectively, have been measured for the first time. The β form is the stronger acid, causing the pH to decrease during mutarotation whenever the equilibrium is approached from the α side. Polarimetric measurements of the catalytic constant should be corrected for the change in pH.Equations are given for kOH, Kiα and Kiβ as functions of the temperature.
Steric effects in the electronic spectra of substituted benzophenones. I: Symmetrically substituted methyl‐benzophenones
Authors: Rekker R. F. , Nauta W. Th. 
Published: September 2010

AbstractThe ultraviolet absorption spectra of benzophenones show well‐defined steric effects arising from ortho‐substitutions.In this paper the experimental data are given for a series of 12 methylsubstituted ketones, including benzophenone.From these data the oscillator strengths f were calculated for the C‐bands; mutual comparison of these f‐values gives and idea of the magnitude of the steric effects caused by ortho‐substituted methyl groups.
The thermochemistry of some redistribution reactions
Authors: Skinner H. A. 
Published: September 2010

AbstractA “redistribution reaction” is defined. The heat of redistribution (ΔHr) is a direct measure of the departure of bond‐energy term values from constancy. ΔHr values are given for examples chosen from hydrocarbon chemistry, and discussed in terms of conjugation and hyperconjugation effects. Other examples from a wider field (including some redistribution reactions of alkyl halides, cyanogen, mercury alkyls, dimethylaminochloroborines) are used to illustrate the influence of polar groups, ionicity, and back‐coordination on bond‐energy variability.
Dérivés azotés du 2‐benzylfluorène et du 2‐(4′‐méthylbenzyl)fluorène
Authors: Buu‐Hoï Ng. Ph. , Royer René , Bisagni Emile 
Published: September 2010

AbstractDans ce travail, on étudie l'arylalkylation du fluorène par les chlorures de benzyle et de p‐méthylbenzyle; en raison du pouvoir cancérogène bien connu du 2‐aminofluorène, la Synthèse de plusieurs dérivés azotés du 2‐benzylfluorène et du 2‐ (4′‐méthylbenzyl) fluorène a été réalisée en vue de leur examen biologique comme substances cancérogènes possibles.
Adsorption and the deposition of carbon on cotton from solutions of sodium dodecyl sulfate
Authors: Vold Robert D. , Phansalkar Achyut K. 
Published: September 2010

AbstractThe deposition of carbon on cotton from solutions of sodium dodecyl sulfate of varying concentration was determined, together with the adsorption isotherms of NaDS on both cotton and carbon, and the aggregate size of the carbon in the suspensions.An optimum concentration for protection against deposition of carbon was found far below the critical micelle concentration, and not correlating with either the presumed values of the zeta‐potential nor the extent of surface coverage by adsorbed detergent. Various explanations were considered and rejected for accounting for the inflection in the adsorption isotherm of NaDS on carbon at the c.m.c., and the subsequent occurrence of a maximum in the isotherm.
Contribution to the knowledge of metanethole IV
Authors: Zanden J. M. V. D. , de Vries G. 
Published: September 2010

AbstractThe structure of some of the compounds mentioned in our investigation of metanethole was still under discussion.It has been found that metanethole has the structure V. When 1‐p‐methoxyphenyl‐2‐methyl‐3‐ethyl‐6‐methoxyindene‐1, formula I, is brominated 2), the product IV is obtained. To the metanethole oxidation product, m.p. 115‐116° 3), formula X 4)5) applies. With hydrazine hydrate it gives XI. Afterwards we also found this substance mentioned in work by A. Müller 5A).The following substances not mentioned in the literature have now been synthesized by us: β‐p‐methoxyphenyl‐β‐m‐methoxyphenylcinnamic acid, m.p. 154‐155°, formula VII, β‐p‐methoxyphenyl‐β‐m‐methoxyphenyl‐β‐hydroxypropionic acid, m.p. 120° (with dec), formula VIII.
The action of ethyl diazoacetate on arylalkyl and dialkyl ethers: (Preliminary communication)
Authors: de Graaff G. B. R. , van Dijck‐Rothuis S. J. H. , van de Kolk G. 
Published: September 2010

AbstractThe results of a preliminary investigation on the action of ethyl diazoacetate on 1‐butoxybutane, 1‐methoxyheptane, and a series of arylalkyl ethers are described.In every case but one, in addition to other processes, a remarkable reaction was observed, yielding the alkoxy or aryloxy derivatives of ethyl acetate.Ethyl phenoxyacetate was formed by the action of the reagent on methoxy‐, ethoxy‐, propoxy‐ as well as isopropoxybenzene; 1,2‐, 1,3‐, and 1,4‐dimethoxybenzene gave ethyl 2‐, 3‐, and 4‐methoxyphenoxyacetate respectively.1‐Methoxynaphthalene yielded ethyl 1‐naphthoxyacetate, but 2‐methoxynaphthalene was not converted into 2‐naphthoxyacetate, ethyl 1‐(2‐methoxynaphthyl) acetate being the chief reaction product.The mixture formed during the action of diazoacetic ester on 1‐methoxyheptane contained the ethyl esters of both heptoxy‐ and methoxyacetic acid.We have started a more extensive investigation on the reaction of ethyl diazoacetate and 1‐butoxybutane. In this case the fate of the alkyl radical expelled during the formation of the alkoxyacetic ester was revealed, since we isolated a considerable amount of butene‐1.
A new synthesis of 2,4,5‐trichlorophenoxyacetic acid (2,4,5‐T)
Authors: Huisman H. O. , Smit A. 
Published: September 2010

AbstractA new synthesis of 2,4,5‐trichlorophenoxyacetic add (2,4,5‐T) is described.A mixture of the insecticidally inactive α‐ and β‐isomers of hexachlorocyclohexane, obtained as a by‐product in the manufacture of the γ‐isomer is converted into 1,2,4‐trichlorobenzene. After converting the 1,2,4‐trichlorobenzene into 2,5‐dichlorophenol, the latter is reacted with monochloroacetic add to 2,5‐dichlorophenoxyacetic add and chlorinated into 2,4,5‐T. The overall yield of 2,4,5‐T calculated on H.C.H. is ca. 40‐50%.
On the reactivity of polynuclear aromatic amines
Authors: Sixma F. L. J. 
Published: September 2010

AbstractThe reaction velocities of a number of aminonaphthalenes, ‐anthracenes, and ‐phenanthrenes with 2,4‐dinitrochlorobenzene in ethanol were measured. It is shown that the logarithm of the reaction constants is inversely proportional to the localization energy or to the charge density at the extra‐cyclic atom as calculated for the hydrocarbon analogues of the amines.
The calculation of some equilibria with alkenes
Authors: van Zijll Langhout W. C. , Korvezee A. E. , Waterman H. I. 
Published: September 2010

AbstractThe thermodynamic quantities of the terms of homologous series in general vary linearly with the number of carbon atoms. Making use of the linear trend of the free enthalpy and, where possible, allowing for a deviation in the case of the lowest terms (initial term effect), we have calculated the composition of a number of equilibrium mixtures in homologous series at temperatures of 300°K−1000°K, and reproduced these compositions in graphs. Deviations from the ideal gas laws and the possible occurrence of liquid have been left out of consideration. As the summation over a limited number of terms leads to relatively simple equations, more complicated equilibria can also be dealt with. Here the following equilibrium mixtures have been calculated:
) n‐l‐alkenes
) n‐l‐alkenes and n‐alkylcyclohexanes, and
) n‐l‐alkenes, n‐alkane‐thiols, and hydrogen sulphide.
The solubility of some normal saturated fatty acids in an aqueous sodium glycocholate solution
Authors: Verkade P. E. , Meerburg W. 
Published: September 2010

AbstractThis paper contains data on the solubility of a number of normal saturated fatty acids (C8‐C15) in a 2.32% aqueous sodium glycocholate solution at 25.0° and 37.0°. The data are discussed with reference to alternation phenomena in homologous series and to the transport of fatty acids through the intestinal wall.
The chemistry of acetylenic ethers XI: Preparation of acetylenic ethers from aldehydes
Authors: Arens J. F. 
Published: September 2010

AbstractA method for the preparation of acetylenic ethers starting from aldehydes I is described. The aldehydes are transformed into α‐chloroethers II and these are halogenated to α,β‐dihalogeno‐ethers III. By means of diethylaniline a molecule of hydrogen halide is eliminated, yielding a β‐halogeno‐α,β‐unsaturated ether IV. From this a second molecule of hydrogen halide can be eliminated by heating with potassium hydroxide, resulting in the formation of an acetylenic ether V.
Peroxidative detoxification of diphtheria toxin studied by using I131
Authors: Agner Kjell 
Published: September 2010

AbstractFrom 50 to 60 different substances ‐ mainly aromatic amines and phenol derivatives ‐ have been tested as to the possibilities to use them as co‐factors in peroxidative detoxification experiments on diphtheria toxin.Results obtained with oxidized I−, admixed with I131−, indicate that the oxidized co‐factors combine with special groups in the toxin molecule.
The metabolism of S35‐ labelled antithyroids in the thyroid gland and other organs of cockerels
Authors: van Erkelens P. C. 
Published: September 2010

AbstractWe studied the metabolism of (S35‐labelled)4‐methylthiouracil and 4‐carboxylthiouracil in the thyroid gland and other organs of cockerels.The main result is that the drugs are nor incorporated in the nucleic acids or in the protein fractions, but that they are oxidized to sulphate.Further, the percentages of the nucleic acids in the thyroid gland and pituitary gland were nor altered by the drugs.
The polarographic estimation of ketosteroids
Authors: Morris C. J. O. R. 
Published: September 2010

AbstractThe technique of estimation of ketosteroids by polarography of their Girard hydrazones is discussed with special reference to the determination of 17 and δ 4:3 ketosteroids.The application of the polarographic method to estimation of urinary 17 ketosteroids is described together with a new rapid procedure employing hydrolysis of the steroid complexes with p‐toluene sulphonic acid.The use of polarography in the determination of individual corticosteroids in human blood is demonstrated and experimental procedures and results described.
Potentiometric determination of chlorides in biological fluids: Microgram analysis
Authors: Sanz Manuel C. , Brechbühler Tony 
Published: September 2010

AbstractA simple electrode system for the determination of a few gammas of chloride in the presence of proteins is proposed. The high‐potential jump at the equivalence point permits the use of a normal valve potentiometer. A. new ultramicro burette is described.
Die photometrische Percuprimetrie von normalen und pathologischen Serumproteinen
Authors: Beck G. , Spengler G. 
Published: September 2010

AbstractIn alkalischer Lösung werden die Proteine von Kaliumcupri‐3‐perjodat oder Tellurat oxydativ abgebaut, indem die Peptidbindungen gesprengt werden, wobei Formiat und Säureamide gebildet werden. Da die verschiedenen Peptidbindungen sich in den Reduktionspotentialen unterscheiden, so reagieren sie verschieden schnell mit CuIII. Wenn man die Oxydation der Proteine in Teiltitrationen auflöst und den Vorgang mit dem Photometer zeitlich jedesmal miszt, so erhält man durch Verbindung der Punkte eine charakteristische Glockenkurve. Bei den Percuprigrammen der Globuline von Carcinomen fanden wir einheitliche Abweichungen vom normalen Kurvenbild sogar bei Präcancerosen. Auch bei Röntgenbestrahlung treten Veränderungen ein, und bei Tuberkulosen kann man andere Veränderungen feststellen.
Über die Möglichkeit der Trennung von Steroiden mittels Papier‐Elektrophorese und Gegenstromverteilung
Authors: Schroeder W. , Voigt K. D. 
Published: September 2010

AbstractDer Fortschritt, der für die Trennung von Steroidgemischen mit Hilfe der Papier‐ und Säulenchromatographie erzielt wurde, ist allgemein bekannt. Die relative Umständlichkeit dieser Verfahren liess uns nach anderen Trennmöglichkeiten suchen. Dabei bot sich die Papierelektrophorese an. Nach Veresterung mit Bernsteinsäurenanhydrid und Darstellung des Natriumsalzes ist eine Trennung sowohl von kristallinen Steroiden als auch von im Harn erscheinenden Steroidabbauprodukten möglich. Da es sich bei den dabei erhaltenen Fraktionen zum Teil noch um Steroidgemische handelt, unterwarfen wir sie der Gegenstromverteilung. Die Auswertung erfolgt UV‐spektrophotometrisch. Die dabei erhaltenen Ergebnisse werden diskutiert.
La Determination De L'Activite Cholinestérasique Du Sang En Vue De La Detection Des Intoxications Par Les Insecticides organo‐phosphores
Authors: Fournel Julien 
Published: September 2010

AbstractLa mesure du pouvoir cholinestérasique du sang chez les personnes en contact avec les insecticides organo‐phosphorés est un moyen de déceler toute intoxication provoquée par l'absorption accidentelle de ces substances avant l'apparition de symptǒmes subjectifs. L'examen systématique du personnel d'un laboratoire de recherches phytopharmaceutiques a permis de mettre en évidence dans quelques rares cas des valeurs cholinestérasiques anormales traduisant une légère atteinte par ces insecticides, ce qui a permis de prendre en temps utile des mesures d'hygiène industrielle convenables.