Rapid analysis of polymer homologues and additives with SFE/SFC-MS coupling

A rapid and easy analysis method for polymers is presented. The method involves sample preparation by SFE, separation of the extracted compounds by SFC and simultaneous quantitative detection by FID, as well as identification of unknowns by MS. The applications illustrate how structural research work and routine polymer analysis can be done with this time saving method.     

From use cases to test cases via meta model-based reasoning

In Use cases considered harmful, Simons has analyzed the logical weaknesses of the UML use case notation and has recommended to “fix the faulty notion of dependency” (Simons: Use cases considered harmful. 29th Conference on Techn. of OO Lang. and Syst., pp 194–203, 1999). The project sketched in this position paper is inspired by Simons’ critique. The main contribution of this paper is a detailed meta model of possible relations between use cases. Later in the project this meta model is then to be formalized in a natural deduction calculus which shall be implemented in the Prolog. As a result of such formalization a use case specification can be queried for inconsistencies as well as for test cases which must be observable after a software system is implemented based on such a use case specification. Software tool support for this method is also under development.     

CLAISEN-Kondensation mit ausgewählten Dithioestern - Synthese spezieller 3-Methylthio-acrylnitrile

CLAISEN -Condensations with Selected Dithioesters - Synthesis of Special 3-Methylthio-acrylnitriles . A useful synthetic route to the mono- and diheteroaryl-3-methylthio-acrylnitriles 1 and 2 is demonstrated by the thioanalogous CLAISEN -condensation. In the presence of sodium hydride in tetrahydrofurane or under PTC-conditions heteroaryl dithiocarboxylic esters 3 react with CH-acidic compounds 4 or 9 to form 3-mercapto-acrylnitriles (e. g. 5 ). Methylation leads to mono- and diheteroaryl-3-methylthioacrylnitriles 1 and 10 (type 2 ). In the same manner tetrathioterephthalic ester 6 reacts with two equivalents of CH-acidic compounds yielding 8 and 11 . By means of spectroscopic methods, especially ¹H- and ¹³C-n.m.r., the structures of the compounds obtained are confirmed.     

Orientation of triblock copolymers in planar extension

Three commercial styrenic triblock copolymers were subjected to planar extension in a lubricated channel die, as a model for the orientation that may occur during processing operations. Materials that contain cylinders of polystyrene show a pronounced orientation of the cylinder axis in the flow direction, as revealed by small-angle X-ray scattering in the three orthogonal directions. This anisotropy produces small-strain tensile moduli that differ by a factor of 10 or more in the two in-plane directions. A material that contains lamellae of polystyrene shows pronounced orientation of the lamellae in the plane of the sample; in particular, lamellar normals are strongly forbidden from pointing along the flow direction. For similar strains, planar extension is much more effective in orienting these materials than simple shear.     

FM+AM’09: workshop on formal methods and agile methods

This workshop aimed at bringing two orthogonal viewpoints about development methods in software engineering together. We were seeking new contributions towards making formal software development faster, and rapid software development more formally sound.     

Contributions to Oil-Spill Detection and Analysis with Radar and Microwave Radiometry: Results of the Archimedes II Campaign

During the Archimedes II campaign in November 1985 (conducted and sponsored by JRC ISPRA) different DFVLR-instruments were flown, an X-band SLAR, an elementary L-band SAR, and microwaveradiometers at 32 and 90 GHz. The objective of these measurements was to evaluate the possibility of detection, localization, and qualification of oil pollution with microwave sensors. Examples of measurement results obtained are presented. As a main result, it can be stated that all of these microwave instruments are valuable and necessary tools for oil pollution detection andoil collection systems.     

Dynamic viscosities of pure tin and Sn-Ag,Sn-Cu,and Sn-Ag-Cu eutectic melts

The dynamic viscosities of the melts of pure tin and eutectic Sn-Ag, Sn-Cu, and Sn-Ag-Cu alloys are studied in heating followed by cooling, and the maximum heating temperature was 1200°C. An irreversible decrease in the viscosity is found in the temperature range 800–1000°C in the polytherms of all melts. This finding is related to the loss of a local order in a melt and can be used to develop temperature regimes for the production of lead-free solders.