Kolloidtechnische Sammelreferate

Ohne Zusammenfassung     

Phosphors?urebestimmung in Superphosphat

Zusammenfassung Unsere Versuche beweisen wiederum die hervorragende Genauigkeit der Ergebnisse, die man mit der Molybdatmethode nach N. v. Lorenz in der von uns empfohlenen Form erhält. Auch die Citrat-Magnesia-methode liefert bei Superphosphaten meist recht brauchbare Werte. Dieser Umstand ist aber nur einem Fehlerausgleich zuzuschreiben, der im vorliegenden Fall allerdings geeignet ist, diese Methode zur Untersuchung der Superphosphate auch weiterhin der Praxis empfehlenswert erscheinen zu lassen.     

Influence of laser beam characteristics and focusing optics on optical laser-induced breakdown detection

Laser-induced breakdown detection (LIBD) is a well established technique for measuring size and concentration of inorganic colloids in liquids. However, most applications of LIBD are restricted to the measurement of mean sizes, which is problematic in cases of wide colloid size distributions (PSD) as typically is the case in natural systems. Evaluation of PSDs from LIBD is possible but requires detailed control of the power density within the laser focus. In the present work we describe the mathematical treatment how to calculate this power density from the beam characteristics of the light source and the optical properties of the focusing optics. The results are compared to measured spatial distributions of breakdown events of three LIBD setups.     

Laser experiments with single atoms and the test of basic quantum phenomena

In this paper, recent experiments of our group performed with single atoms in cavities and traps are summarized. In the first part, experiments with the one-atom maser are described dealing with the generation of number states of the photon field. In the second part of the paper, the spectroscopy of a single trapped In⁺ ion is discussed being performed with the aim of realizing a new frequency standard in the optical range.