Amsterdam- London-New York 1970. 1st Edit., 506 pp., bound, Dfl. 70.00. "Metastable ions", i.e. ions which decompose on the way from the ion source to the collector, play an important role in the investigation of mass-spectrometric decomposition processes because they yield information on cleaved-off particles. Metastable ions lead to the formation of relatively broad bands in the corresponding mass spectra. However, the low intensity of such bands makes them difficult or impossible to detect.To facilitate the task of detecting metastable ions Beynon, one of the authors, has evolved an elegant method: normal ions from the ion source of a double-focusing apparatus pass through the field-free space with a kinetic energy E into the electrostatic sector field. In contrast, metastable ions, which are decomposed in the field-free space, carry only the fraction F = Em2/ml of the kinetic energy of the parent ions, ml being the mass of the parent ions and m2 that of the daughter ions. These ions can only pass through the retarding potential if the voltage V in the electrostatic sector field is reduced to the value Vm2/ml. If the voltage is continuously changed from 0 to V, one obtains a spectrum of the kinetic energies of all metastable transition processes. Since in this case there is no overlap with the normal spectrum, this technique constitutes a very sensitive method for investigating metastable ions. With the aid of the present tables the corresponding metastable transition processes can easily be determined from the kinetic energy values, which can be read off directly. This book will therefore be an indispensable and time-saving tool for all laboratories in which IKE (ion kinetic energy) spectra are used for the study of metastable ions.Spiteffer [NB 923 IE] Disinfection. Edited by M. A. Bernarde. Marcel Dekker, Inc.This book demonstrates that disinfection still belongs to an underdeveloped area of research. In many cases ultraconservatism -"disinfection rituals" -stands in the way of the few new possibilities in the field of disinfection. In practice, disinfection IS primarily a question of money and of suitable staff. The book is aimed at all people working in research, hygiene, and the foodstuffs industry who are interested in new discoveries in the field of disinfection. Nineteen authors have contributed to the book, most of them giving detailed reports on specialized fields. The collaboration of the team of authors, however laudable in itself, sometimes leads to overlapping and unnecessary repetition.One is inclined to divide the book into a theoretical and a practical and technical part. The first part would have been improved by condensing some parts and expanding others. Bacterial metabolism and mechanisms of action should perhaps have been put in one chapter and the sites of action of the common disinfectants and (in somewhat more detail) those of some antibiotics could have been included in the metabolism and biosynthesis schemes. A few basic theoretical aspects could also have been transferred from ...

\. asicinin, ein bronchodilatorischer Wirkstoff aus Adhtodn Vasicn Nees, einem immergrunen Busch, dessen Blatter in der Eingeborenen-Medizin Indiens als Heilmittel bei Erkaltungen, Husten, Bronchitis und Asthma verwendet werden, wurde von D. R. MeAtn, J. S. Nornvarte und R. M. Desoi isoliert, die seine Struktur aufklarten. Vasicinin (I), C11H10N202, Fp = 200-201 "C, [%]h2 = -100" (0.5 : , i in Chloroform), (Hydrochlorid Fp = 232-234 "C), ist 2.3(a-Hydroxytrimethylen)-4chinazolon, was aus der Identitat des Naturstoffes mit der durch Oxydation von Vasicin, CllH12N20, mit 30-proz. HzO2 erhaltenen Substanz folgt. Bei der Oxydation tritt leicht Racemisierung ein. Sowohl (-)-wie (-:)-Vasicinon sind aktive Bronchodilatoren, Vasicin dagegen ein Bronchoconstrictor. /

A series of polyunsaturated vinyl-hydrocarbons (n-C15 to n-C17) (10, 11, 12, 15, 16 and 17) including the as yet unknown all-cis-1,7,10,13-hexadecatetraene (15) as well as some rare sesquiterpenes such as isocomene (8) or modhephene (7) have been isolated from the root oil of Senecio isatideus. Unambigous positioning of the double bonds of the polyolefines was easily established by 13C-NMR spectroscopy [16]. A new mass spectroscopical method utilizing NO as a reactant gas for chemical ionization [1] made possible the reliable identification of minor and trace constituents without any chemical pretreatment or further derivatisation.

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