Lust auf Zukunft

„Chemie schafft neue Strukturen”︁ ‐ das Motto der GDCh‐Jahrestagung die chemische Industrie. Mit welchen Strukturen die BASF in den letzten 140 Jahren die BASF geblieben und The Chemical Company geworden ist, erläutert im Gespräch der Vorstandsvorsitzende Jürgen Hambrecht.     

The Monodromy Matrix Method of Solving an Exterior Boundary Value Problem for a Given Stationary Axisymmetric Perfect Fluid Solution

A procedure is described for matching a given stationary axisymmetric perfect fluid solution to a not necessarily asymptotically flat vacuum exterior. Using data on the zero pressure surface, the procedure yields the Ernst potential of the matching vacuum metric on the symmetry axis. From this the full metric can be constructed by established procedures.     

A new method forq-hypergeometric series

We reintroduce a notation of Heine, which leads to a new method for computations and classifications ofq-special functions. The main topic of the new method is an involution operator on the set of allq-shifted factorials. Presented at the 10th International Colloquium on Quantum Groups: “Quantum Groups and Integrable Systems”, Prague, 21–23 June 2001.     

Size distributions and synthesis of nanoparticles by photolytic dissociation of ferrocene

Iron-containing nanoparticles were made by laser-assisted (ArF excimer laser, λ=193 nm) photolytic dissociation of ferrocene (Fe(C₅H₅)₂ or FeCp₂) in argon and an oxygen/argon gas mixture. The particle-size distributions were obtained on-line by using differential mobility analysers (DMAs) and were found to be log-normal with a geometric standard deviation of 1.85. In argon, particle sizes between 3 and 100 nm were generated. The volumes of these particles were found to increase linearly with the increased repetition rate, fluence and beam size of the laser. These observations are explained on the basis of the residence-time approach model. Received: 23 November 1999 / Accepted: 19 September 2000 / Published online: 22 November 2000     

抽运激光聚焦特性对预脉冲诱导的类氖J=0→1 X射线激光近场像的影响

研究了在最佳除焦、预脉冲光束单独散焦及主预脉 时散焦三种不同抽运激光聚焦条件下,预脉冲诱导的类氖铁和锌Ｊ＝０→１Ｘ射线激光的近场像。本实验是在Ａｓｔｅｒｉ ｉｖ磺激光装置上进行的,实验中主、预脉冲间的时间间隔为５ｎｓ。实验发现在抽运激光主、预脉冲最佳聚焦条件下,Ｘ射线激光束在２．５ｃｍ长的线状等离子体输出端沿靶面（垂直）方向分裂成两束;在抽运预脉冲单独散焦条件下,仍然观察到这一分裂现象;但是当抽运