Die Chlorierung von Hexachlor‐p‐xylol (I) mit gasförmigem Chlor in Chlorsulfonsäure in Gegenwart von 5% Iod ergibt bei einer Reaktionstemperatur von 30°C eine 85%ige Ausbeute an Tetrachlorterephthalsäuredichlorid (II).

The nanofiltration of the water-ethanol mixture of different compositions at three pressure drops through a nanoporous membrane based on poly(1 trimethylsilyl 1 propyne) has been experimentally and theoretically studied. A mathematical model of the onset of flow has been proposed, and the percolation threshold depending on the physicochemical and geometrical characteristics of the membrane system has been found. The model suggests gradual membrane pore opening with an increase in pressure and alcohol concentration in the mixture and can take account of the distribution of alcohol molecules over the cross sec tion of the membrane pores. The theoretical results agree well with the experimental data.

Recent developments in TlBr material preparation and growth technology have led to much improved crystal quality, detector performances and most importantly, reproducibility. In this paper, we describe some of the technological steps we have developed that have allowed us to produce reproducible spectrometric grade crystals for detector applications and present spectroscopic results. Typical crystals have a specific resistance of (3 5) 10 11 Ohm-cm and mobility-life time products of about 10 4 cm 2 /V, for both electrons and the holes. After fabrication into simple planar detectors of area 5 5 mm 2 and thickness 2 mm, spectral resolutions of 0. 8, 1.4, 2.1, and 7.1 keV, have been achieved at incident energies of 5.9, 59.6, 122, and 662 keV, respectively. These results were obtained without collimation or employing single carrier sensing or depth correction techniques.

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