Die Ermittelung des Basizitätsverhältnisses von Samarium und Gadolinium durch quantitative Röntgenanalysen

Abstract

Im Gebiete der Seltenen Erden (von der Ordnungszahl 57–64) sind quantitative röntgenanalytische Bestimmungen durch Vergleichung der wahren Intensität der Lα1‐Linien gelegentlich mit großer Genauigkeit, in vielen Fällen aber ohne große Febler ausführbar, wenn die Atomkonzentrationen den Linienintensitäten proportional gesetzt werden. Die wahren Linienintensitäten müssen aus den beobachteten photographischen Schwärzungen berechnet werden. Besonders genau analysierbar sind Gemische von Praseodym und Neodym, während besonders ungunstig die Analysenergebnisse bei cerhaltigen Gemischen ausfallen.

A natural periodic system including the rare earths

“…These three elements are also characterized by their colorless salts, sparingly soluble double alkali sulfates (a distinction of Y from the so-called yttrium earths), single isotopes (21), lower paramagnetic susceptibilities, absence of absorption spectra in the visible, doublets in the spark spectra (22), and band spectra of ScO, YO, and LaO (23). Also from the standpoint of basicity Y should be followed by La more closely than by Lu because basicity increases downward for succeeding elements in a given column and, since the basicity of the rare earths decreases from left to right, Lu is less basic than Y, the value of the latter being between Nd and Sm (24), (25). Similar conclusions are indicated by the work of Rolla and Piccardi (26) on ionization potential data.…”

Analytical chemistry

“…85 Triketohydrindene hydrate is not a trustworthy reagent for the products of protein hydrolysis. 86 The action of iodine and bromine on unsaturated barbituric acid derivatives in bicarbonate solution is described ; 87 " veronalides " are diagnosed micro-crystalloscopically. 88 Alkaloids are classified in nine groups according to their sensitivity towafds precipitating agents, their solubility in water and the basic strength of the free alkaloids; 89 a tabulation is made of the microchemical reactions of 78 alkaloids with a number of reagents.90 Limiting concentrations for the micro-precipitation of alkaloids by sodium alizarinsulphonate are recorded ; 91 sulphonic acids of other anthraquinone derivatives form crystalline precipitates with organic bases.92 Microchemical methods are described for the detection of strychnineJS3 I-ephedrine and ephet~nine,~~cytisine,~~ echinopsine,96 nicotineJS7 c o l c h i ~i n e , ~~ piperineJ99 and choline.1 The formation of the substance responsible for the thalleioquinine reaction is retarded by a decrease in p,.…”