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The highly endothermic reaction NHS + CH4 = HCN + 3H2 + 60 kcal, which is technically realized in tube reactors with wall catalysis, is investigated. With the aid of special quartz probes, concentration profiles as function of the tube length and the tube radius are determined at different throughputs, together with the temperature distribution along the tube axis. Flow type, heat and mass transfer, as well as a macrokinetic model, are estimated. Concentration curves calculated with those data for extreme conditions "envelope" the measured concentration profiles. The parameters limiting the overall reaction are elucidated.Hydrogen cyanide is industrially produced according to the so called "BATA process," using ceramic tubes of 2000 mm

The electron impact mass spectra of cyclophosphamide (1) are very sensitive towards experimental conditions in view of the kind of sample handling, the type of mass spectrometer used and the temperature of evaporation. The reason for this phenomenon is the elimination of HCl from the molecular ion by a specific 1,5-hydrogen transfer yielding an ion at m/z 224 which is structurally related to the bicyclic compound 4 with its typical fragment ions at m/z 175 and 147. Thermal excitation of the sample increases the intensity of this fragmentation pathway. The fragmentation pattern of 1 and the thermally induced rearrangement reaction has been elucidated by means of isotopic labelling, high-resolution data, metastable ion analysis and some tandem mass spectrometric experiments. Various samples of 1 monohydrate and its commercially available preparations, which are triturates with sodium chloride, differing in the crystal size distribution, showed nearly identical mass spectra on two different magnetic mass spectrometers, provided that the materials were introduced as solids under careful control of the evaporation temperature. The fragmentation via m/z 224 prevails in case of non-crystalline, pre-dissolved samples on one of the instruments used which might be explained by a differing construction of the ion source and the sample cup holder. The conclusions of Mruzek et al. concerning different proportions of stereoisomers in pharmaceutical preparations of 1 lack any analytical evidence.

A simplified model describing the polymerization of formaldehyde in aqueous formaldehyde solutions has been developed basing on results taken from 'H-NMR-measurements. It is shown that a model with only one equilibrium constant is sufficient to describe the molecular weight distribution in aqueous formaldehyde solution.

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