Surface magnetism of Fe(110) from polarized electron scattering

Exchange- and spin—orbit-induced scattering asymmetry spectra of polarized slow electrons from the ferromagnetic Fe(110) surface have been calculated by dynamical theory and found to agree with recent experimental data taken at room temperature. Comparison of exchange asymmetry spectra, obtained for various interaction and layer-dependent magnetization models, with the data implies firstly an enhancement of the surface magnetization by about 30% with respect to the bulk, and secondly the importance of spin-dependent localized inelastic electron—electron scattering processes.     

Caesium-selective PVC membrane electrodes based on bis(crown ether)s

Caesium-selective PVC membrane electrodes based on bis(crown ether)s containing benzo-18-crown-6 moieties were prepared using two kinds of plasticizers. Selectivity coefficients for various interfering monovalent ions were determined by the mixed solution method, and were found to relfect the complexing property and extractability of the bis-(benzo-18-crown-6)s. The electrochemical selectivity was also compared with that of the corresponding monocyclic analog and valinomycin.     

Determination of germanium by hydride generation with reducing tube followed by graphite furnace atomic absorption spectrometry using CH4/Ar as sweeper gas

Summary A sensitive method for the hydride generation and graphite tube furnace atomic absorption spectrometric measurements with a reducing tube using mixed gas (CH₄ 10% + Ar 90%) as sweeper gas has been developed for the determination of germanium. Germanium hydrides were generated in a horizontal glass tube, in which a pellet of NaBH₄ was placed. 0.61/min of sweeper gas flow rate, 2,700° C of atomization temperature and 2.5–3 M of acidity range were the best experimental conditions. The strong supression of the germanium signal by Ni and Co was effectively eliminated with 1,10-phenanthroline and thiosemicarbazide was comparatively effective for Au. The reducing tube used in this technique is extremely simple and can be connected to all the types of graphite furnaces. A detection limit of 2 ng was obtained with a precision of 3–4%

---

Germaniumbestimmung durch Hydriderzeugung im Reduktionsrohr und nachfolgende Graphitofen-AAS mit CH₄/Ar als Spülgas

Zusammenfassung Bei dem beschriebenen Verfahren werden die Hydride in einem horizontalen Glasrohr erzeugt, das eine NaBH₄-Perle enthält. Als optimale experimentelle Bedingungen ergaben sich: Spülgas (0,61/min) aus 10% CH₄ und 90% Ar, Atomisierungstemperatur 2700° C, 2,5–3 M Säure. Die starke Beeinflussung des Ge-Signals durch Ni und Co wurde mit Hilfe von 1,10-Phenanthrolin eliminiert, die Störung durch Au mit Hilfe von Thiosemicarbazid. Das verwendete Reduktionsrohr ist sehr einfach und kann für alle Arten von Graphitöfen benutzt werden. Die Nachweisgrenze beträgt 2 ng, die Reproduzierbarkeit 3–4%.

---

---

Paper read at the Meeting of the Japan Society for Analytical Chemistry, June 1982     

Regularized determinants for quantum field theories with fermions

A new type of regularized determinant for the ratio of two Dirac operators is presented. Some of its properties with application to the chiral anomaly are given.