AbstractA convenient route for the introduction of mercaptan groups into nitrogen‐containing polymers is provided by addition of propylene sulfide to such polymers. The reaction with polyethylenimine, Versamid 140, and nylon 11 was investigated. In contrast to the reaction of polyethylenimine with propylene oxide, only limited initiation of the grafting reaction on the polymeric amine is achieved, as evidenced by a low mercaptan functionality of the grafted products.

Two band systems of the BS molecule, called the α and γ systems, have been excited in a discharge through B2S3 vapor in a quartz discharge tube. Vibrational and rotational analyses of these systems have been carried out, and it is shown that both systems have the same lower state, which is a 2Σ state. Both the upper states are 2Π states. The α system is analogous to the α system of BO, but the γ system has not been observed for BO. Tables giving the vibrational and rotational constants of the various states are given. A third system of strong bands in the blue–green region is observed simultaneously with the α and γ bands in the discharge. These bands have not yet been interpreted. By means of the observed isotopic bands, it has been proved that BS is the emitter of the α and γ systems.

SOME time ago the spectrum of tantalum was chosen as a subject of investigation in this Laboratory. The hyperfine structure of the spectrum of tantalum had not been dealt with in the literature of the subject, so far as we are aware.

FOR some time the spectrum of rhenium has been the subject of investigation in the Amsterdam Laboratory “Physica”. With the Bulger E1 quartz spectrograph we have studied the spectrum of the arc and of the underwater spark. The hyperfine structure and the magnetic resolution have been investigated with the 20-ft. grating in an Eagle mounting.

IN connexion with the forthcoming celebration of the centenary of Faraday's greatest discovery, which predominantly has influenced our concepts of Nature and our present electrical industry, there is room in NATURE for an article on magneto-optics which may also direct attention to Dutch scientific work in relation to Faraday's researches and discoveries.

Neuere Untersuchungen über die Hyperfeinstruktur der Wismutbogenlinien und ihren Zeemaneffekt, welche die früheren Ergebnisse ergänzen und bestätigen. Bemerkungen über das Termschema des Wismuts. Intensitäten in den Hyperfeinmultipletts. „Verbotene“ Komponenten im Paschen — Back — Effekt der Hyperfeinstrukturen.

Der Zeemaneffekt von 110 Ar II-Linien ist untersucht. Die von einem von uns (de Bruin) gegebene Analyse ist an dem Zeemaneffekt geprüft. Es folgt aus dem Zeemaneffekt, daß im Spektrum des ionisierten Argons normale und anomale Kopplungen auftreten; in den höheren Energieniveaus ist die Kopplung anomal. Für einige Termgruppen ist der „g-Summensatz“ geprüft.

SEVERAL lines of the scandium spectrum have been classified by Catalán (An. Soc. Esp., 20, 606, 1922, and 21, 464, 1923). According to him, the Sc I. spectrum contains a doublet- and a quartet-term system; the Sc II. spectrum a triplet-system. It is, however, probable that some corrections must be made in his term-scheme. These corrections are, obviously also made by Gieseler and Grotrian (Nature., 12, 438, 1924).

THE quantitative relations between the spectra of argon and ionised potassium have been for some time a subject of investigation in the Amsterdam Laboratory. The available observations are chiefly due to Schillinger (Wiener Sitz. Ber. 118, 605, 1909), McLennan (Proc. R.S., 100, 182, 1921), and Dik and Zeeman (Proc. Kon. Acad. Amsterdam, 1922, 1923). Schillinger used a spark for the production of the K+ spectrum, McLennan, as well as Dik and Zeeman, the electrodeless discharge. Dik and Zeeman got a rather pure K+ spectrum, because with very intense discharges the arc lines were entirely suppressed, a result at variance with that of other observers. The observations were obtained with a quartz spectrograph. The accuracy is, therefore, not sufficient for a scrutinising analysis, and observations with a grating spectrograph were projected.

THREE optical effects of motion are known at the present time, namely, (i) astronomical aberration, discovered by Bradley in 1728; (2) the Doppler effect expressing the dependence of the wave-length of light on the relative motion of a source and an observer; (3) the effect of the carrying along of light by motion in a straight line of transparent matter, or the Fizeau effect, and a cognate effect of a rotation. Sir Oliver Lodge showed that the ether between two rapidly revolving steel discs is not put in motion.

BY Zeeman and Dik (Proc. Amsterdam 25, 67, 1922), and Dik and Zeeman (Proc. Amsterdam 26, 500, 1923), it was found that in the electrodeless discharge (observations of McLennan, Dik and Zeeman) most of the lines of ionised potassium between 6594 Å and 3063 Å could be arranged in quadruplets.

Annalen der PhysikVolume 376, Issue 9-12 p. 199-203 Article Weitere Beobachtungen über eine Beziehung zwischen den Spektren des ionisierten Kaliums und des Argons P. Zeeman, AmsterdamSearch for more papers by this authorH. W. J. Dik, AmsterdamSearch for more papers by this author P. Zeeman, AmsterdamSearch for more papers by this authorH. W. J. Dik, AmsterdamSearch for more papers by this author First published: 1923 https://doi.org/10.1002/andp.19233760916Citations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinked InRedditWechat Citing Literature Volume376, Issue9-121923Pages 199-203 RelatedInformation

IN two papers published in the Proceedings of the Amsterdam Academy (vol. xvii., 445, 1914; vol. xviii., 398, 1915) an experimental investigation concerning Fresnel's convection-coefficient for light of various colours was described. The main object of my repetition of Fizeau's experiment, in the improved form introduced by Michelson, was to decide between the expressions for the convection-coefficient given by Fresnel and by Lorentz. As a review of the papers mentioned has appeared in NATURE (vol. xcvi., 430, 1915), I may be permitted to give here a short account of further progress. It may suffice to recall that my results were largely in favour of the Lorentz expression with the dispersion term. For the wavelength 4500 U the difference between the two expressions under consideration amounted for water to quite 5 per cent. The probable error of the experimental result was estimated at somewhat less than 1 per cent.