Charakterisierung der stabilität von modifizierten polypropylen-glasfaser-verbunden nach thermo- und photooxidation

For the purpose of being compounded with glass fibres, homopolymers and polypropylene chemically functionalized in different ways were characterized with regard to their thermooxidative and photooxidative stabilities, after having been subject of different manners of stabilization. Consequently, in the basic state and after short ageing times, the compounds stabilized with 0.10% BHT, 0.30% DSTP, 0.05% Irganox 1010, and 0.25% Tinuvin 770 exhibit the best thermooxidative and mechanical stabilities. This effect is lost with increasing periods of ageing. Concerning the modifier it can be said that the samples functionalized with a mixture of acrylic acid and maleic anhydride in 5 : 1 ratio show the best thermooxidative and mechanical behaviour; on the other hand, the photooxidative behaviour is the worst. Pure maleic anhydride modifier leads to a significant worsening of the thermooxidative and mechanical properties, the UV stability is not changed against the unmodified samples. Glass fibres cause a significant improvement of the compound properties — particularly when applying a modifier —, a considerable retardation of the thermooxidation period as well as a decrease of the photostability. The latter influence is, however, not completely clear.     

Object recognition by three-dimensional curve matching

Experimental results for the recognition of general curves in three-space using registered range and intensity images are presented. the matching algorithm uses fast Fourier transforms to determine the least-squares difference between sequences of points sampled at equal intervals along two piecewise linear approximations of curves in three-space and returns the rotation and translation required to bring one of the curves into closest juxtaposition with the other. Performance of the algorithm is demonstrated by matching curves in three-space which are the boundaries of regions of contrasting reflectivity on curved surfaces. the experiments use a recently developed range sensor which is able to generate a 512 × 460 × 12 bit range image (with registered intensity image) in 40 s.     

Tracing atmospheric nitrate deposition in a complex semiarid ecosystem using delta17O

The isotopic composition of nitrate collected from aerosols, fog, and precipitation was measured and found to have a large 17O anomaly with delta17O values ranging from 20 percent per thousand to 30% percent per thousand (delta17O = delta17O - 0.52(delta18O)). This 17O anomaly was used to trace atmospheric deposition of nitrate to a semiarid ecosystem in southern California. We demonstrate that the delta17O signal is a conserved tracer of atmospheric nitrate deposition and is a more robust indicator of N deposition relative to standard delta18O techniques. The data indicate that a substantial portion of nitrate found in the local soil, stream, and groundwater is of atmospheric origin and does not undergo biologic processing before being exported from the system.     

Korrosionsverhalten und Deckschichtbildung auf Kupfer und Kupferlegierungen

Corrosion Behaviour and Film Formation of Copper and Copper Alloys Film formation processes on Cu, CuZn, CuAl and CuNi materials in NH₃- and Cl^?-containing aqueous solutions are discussed in a summary article by way of corrosion systems, some typical and some of practical significance, and the protection offered by these films against general corrosion is described. Also considered are localized corrosion phenomena to which Cu-base alloys with oxide films are typically exposed. A comparison of the resistance of the various alloying systems illustrates the particular danger of stress corrosion cracking of mechanically stressed metals. Finally, the type and structure of oxide surface films are discussed with respect to their effect on crack initiation.     

Some comments on a Viennese school of psychiatry.

The author comments on a school of psychotherapy called Logotherapy or Existential Analysis, which was originated by Victor E. Frankl of the Department of Neurology and Psychiatry at the University of Vienna. This school of analysis reflects the culture of the Hitler era and post-war Europe. Frankl states that neurosis is caused by repression of the patient's sense of responsibility and the function of psychotherapy is to bring this sense of responsibility back to the patient's awareness. Happiness, he postulates, is a byproduct of the realization of other values. Fear of death, aging, and discomfort are the principal causes of anxiety. The author feels that this school of psychotherapy, which has arisen from an experiential background so different from ours is worthy of careful study. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of assigned goal level and knowledge of results on arithmetic computation: A laboratory study.

Examined the effects of knowledge of results (KR) and assigned goals on arithmetic computation. 100 female university students either received or did not receive explicit KR while under an easy or challenging goal assignment. 50 controls received neither KR nor goal assignment. Ss receiving KR under challenging goal assignments significantly increased their computational speed at no apparent cost in accuracy. These findings are congruent with the findings of M. Erez (1977). With the minimizing of implicit KR in the no-KR groups in the present study, challenging goal assignment in itself had no noticeable effect on computational speed and led to a significant increase in errors. It is suggested that feedback may be a necessary complement to assigned goals in facilitating performance. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Schnellbestimmung monomerer,nicht oxidierter Fettsäuren

Quick Determination of Monomeric Unoxidized Fatty Acids Refining and distillation fatty acids as well as raw or partly refined oils can contain beside monomeric fatty acids di and polymeric as well as oxidized fatty acids, too. Determination of the content of monomeric, unoxidized fatty acids is important for the use in feed. As quick method a gas chromatographic procedure is presented. Collaborative studies demonstrate a satisfactory repeatability of the results. The comparability is impaired by apparatus and operating parameters. The relative constance of deviation permits a compensation by comparative analysis and determination of correction factors.