Shaped charge jet interaction with Highly Effective Passive Sandwich Systems - experiments and analysis

The development and investigation of reactive sandwich targets and their interaction with shaped charge jets is one of the many research areas, where important contributions were made by Manfred Held. Such reactive sandwiches are known to be extremely effective against jets, but have a number of disadvantages. In this work, the interaction of the copper jet from a shaped charge calibre 136 mm with a double sandwich system, each sandwich consisting of a non-reacting layer between outer steel plates, is investigated. In 10 experiments with identical geometrical setup, only the material of the non-reacting layer is changed. Using flash X-ray pictures, the interaction of the jet with the sandwich system is investigated. Evaluation of these pictures as well as the comparison of the measured residual penetrations behind the sandwich target clearly demonstrate the influence of the material of the inner sandwich layer. The deformation and movement of the steel plates, caused by the penetrating jet, can be seen in the X-ray pictures. It is shown that it is possible to distort a shaped charge jet so that its penetration capability behind the target is reduced to a minimum. A fully three-dimensional hydrocode simulation of the experiments enabled the jet/sandwich interaction and steel plate deformation and rupture to be studied in detail.     

Replay-based debugging of occam programs

Parallel programs are intrinsically non-deterministic, and therefore the techniques of cyclical debugging that are commonly used for sequential programs are not suitable for parallel ones. This paper proposes a method to reproduce Occam program behaviour. Saving information on the timer values input by the program and the guards selected at run-time on alternative commands allows program replay, i.e. it makes it possible to re-execute the program deterministically with the same inputs following the same instruction path. This enables the software developer to use tools such as debuggers and intrusive monitors to help identify program faults. After discussing possible implementations of the proposed technique, IRD (an interactive replay debugger for Occam programs) is described. Finally, the use of the IRD in a sample debug session is presented as an example.     

Ein Beitrag zur Biosynthese amylosereicher Erbsenstärken

Contribution to the Biosynthesis of High-amylose Pea Starches Biosynthesis of starch is a complex process but few details are still unknown. This paper describes an investigation upon pea starch biosynthesis. Peas as a source of starch offer two qualities, a pea starch with 40% amylose content (smooth pea starch) and a pea starch with more than 60% amylose content (wrinkled pea starch). Samples for analysis were taken during growth. According to the quantitative determination of starch and amylose the accuracy of amylose detection was tested. Furthermore a qualitative analysis was carried out by molecular weight estimation of the starch. Both kinds of peas showed a high amylose synthesis during the last few days of growth, whereas amylopectin synthesis was highly in earlier stages. Wrinkled peas have shown only little synthesis activity of amylopectin during maturity. Therefore the amylose content of these peas was higher, instead of equal amylose synthesis quotas of both smooth and wrinkled peas.     

Spektroskopische Untersuchungen an organischen Carbonylverbindungen. VI. NMR-Studien an substituierten β-Diketonen und ihren vinylogen Derivaten

Spectroscopic Investigations on Organic Carbonyl Compounds. VI. N.M.R.-Studies on Substituted β;-Diketones and their Vinyloge Derivatives . ¹³C- and ¹H-n.m.r.-data of substituted β-diketones and their vinyloge derivatives are presented. Most of the compounds exist chiefly in the enol-form. Only in the case of 4-dimethyl-aminodibenzoylmethane a keto-enol-equilibrium is registered. The influence of the substituent A and the chainlength on the position of the enol proton is discussed.     

Kristallin-flüssige 1,3,4-Thiadiazole. II [1]. 1,3,4-Thiadiazole mit Cyclohexanstrukturfragmenten

Liquid Crystalline 1,3,4-Thiadiazoles. II. 1,3,4-Thiadiazoles with Cyclohexanefragments Preparation and liquid crystalline properties of disubstituted 1,3,4-thiadiazoles (1 and 2) are described. The mesomorphic behaviour of the title compounds is compared with their benzoate analogues. The dielectric anisotropy of these compounds is negative.     

Alkylthio-substituierte Bis(benzol-1,2-dithiolato)zinkate,Benzol-1,2-dithiole und -1,2-dithiolate – Edukte für Dibenzo[c,g](1,2,5,6)tetrathiocine und Benzo[c](1,2,3)-trithiole; Untersuchungen zu Benzodithieten und ortho-Dithiobenzochinonen

Alkylthiosubstituted Bis(benzene-1,2-dithiolato)zincates, Benzene-1,2-dithioles, and -1,2-dithiolates – Educts for Dibenzo[c,g](1,2,5,6)tetrathiocins, and Benzo[c](1,2,3)trithioles; Investigations on Benzodithietes and ortho-Dithiobenzochinones Using benzenehexathiolate 1 it is possible to synthesize alkylthio-substituted benzo-1,3-dithiole-2-thiones 2 , or -ones 3 and benzo-di(1,3-dithiole-2-thiones) 4 , or -ones 5 , resp., which were cleaved under basic conditions. The generated benzene-1,2-dithiolates 7 were isolated as benzene-dithiolato zincates 8 , benzene-1,2-dithioles 11 , and benzene-1-thiole-2-thiolates 10 . Dibenzo[c,g](1,2,5,6)-tetrathiocins 9 were synthesized by oxidation of 7 or 8 in good yields. For the per(methylthio)-substituted tetrathiocin 9a the twist conformation was proved by x-ray structure analysis. The tetrathiocin 9a was probably formed via the orthodithiobenzoquinone 13a . Photolysis of 3a at room temperature in solution led to 9a and tetrakis(methylthio)benzo[c] (1,2,3)trithiole 12a as the main product, which was also formed by irradiation of 9a . The trithioles 12 were formed from 8 by reaction with sulfur dichloride. 12a was investigated by x-ray structure analysis. ortho-Dithiobenzoquinone 13c can be claimed as an intermediate upon irradiation of benzo-1,3-dithiol-2-one 3c in an argon matrix at 10 K. Depending on the wavelength the equilibrium lies either on the side of dithiobenzoquinone 13c or benzodithiete 14c . The same is true for system 15/16 , which can be reached by flash vacuum pyrolysis of 3c .