Colorimetrische Bestimmung der Phosphors?ure in Tonerdeprodukten

Zusammenfassung Es wird eine colorimetrische Bestimmung von Phosphorsäure in Tonerdeprodukten beschrieben; entsprechende Arbeitsvorschriften werden gegeben. Diese Art der Bestimmung hat den Vorteil, dass sie schneller und einfacher zu handhaben ist als die gravimetrische Methode.     

电致发光显示器的国内外发展现状和研究动向

这篇调研报告是为我所应四机部显示会议的邀请在会上作关于电致发光器件(不包括发光二极管)国内外水平的综述报告提供的参考资料.本文的依据是截至1981年5月我室收集到的各种公开发表的文献和消息报导.反映的基本上是1980年达到的水平.     

Measurement of thermal conductivities of soils

Energy conservation in buildings, in particular in underground constructions, is strongly affected by the thermal properties of the soil surrounding such buildings. Experimental results of thermal conductivity studies of different soils are reported based on a quasisteady method [1]. The soil sample is placed in the annular space between two concentric tubes and is heated uniformly on the inside wall keeping the outside wall insulated. Four different types of soils (Moon Valley, River Sand, In-situ, and Ridgedale), are studied over a temperature range from ?5°C to 30°C for three different densities and moisture contents ranging from 0.5 to approximately 12% (by weight). The results indicate that the moisture content is by far the most important parameter. The thermal conductivity may increase by almost an order of magnitude as the moisture content increases. In addition, there may be a strong variation of the thermal conductivity in the phase transition region from unfrozen to frozen soils.     

Mathematical analysis of a simple model for the stripping reaction

Zusammenfassung Die Integralgleichung (1.6), die aus einem sehr vereinfachten Modell der stripping reaction hergeleitet ist, wird diskutiert. Es ist bemerkenswert, dass die bekannte Methode vonN. Wiener undE. Hopf auf diese komplizierte Integralgleichung angewendet werden kann. Die entstehende Funktionalgleichung (1.12) wird im § 2 auf die lösbare Differenzengleichung (2.20) reduziert. § 3 behandelt die Eindeutigkeit der Lösung und § 4 die explizite Lösung in einem Spezialfall. Die explizite Lösung des allgemeinen Falls wird nicht angegeben.

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Most of the content of this paper grew out of discussions, which the author had withJ. H. D. Jensen, J. M. Luttinger, andT. H. Berlin during their respective stays at the Institute for Advanced Study. The author's only merit consists in having written down the results.

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Institute for Advanced Study.     

Laudatio to the 60th birthday of Rudolf Haag

Ohne Zusammenfassung

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Laudatio to the 60th birthday of Rudolf Haag

     

Laser ablation of energetic polymer solutions: effect of viscosity and fluence on the splashing behavior

Laser plasma thrusters are a new kind of propulsion system for small satellites, and work with the thrust created by the laser ablation of a target. Liquid polymer solutions are very promising fuels for such systems, provided that no splashing of the target occurs, because ejection of droplets strongly decreases the performances of the system. We have investigated the nanosecond infrared laser ablation of glycidyl azide polymer solutions containing carbon nanoparticles as absorber. Shadowgraphy imaging revealed two cases, namely splashing regime and solid-like behavior. The transition between both regimes depends on the viscosity of the solution and on the laser fluence, and is explained by the recoil force acting on the target. Appropriate conditions to avoid splashing were identified, showing that this liquid polymer solution is a suitable fuel for laser plasma thrusters.     

A correspondence between IBA-1 and IBA-2 models and electromagnetic transitions in the decay of some erbium isotopes

The interacting boson approximation IBA-1 model space, in which neutron and proton degrees of freedom are not distinguished, can be considered as a subspace of the IBA-2 model space. Using the microscopic background of the IBA-2 model, a correspondence can be established between IBA-1 and IBA-2 model space. Since the space of the IBA-1 model can be regarded as a subspace of the IBA-2 model there is a unique way to ‘Project’ the operators of the IBA-2 model onto those of IBA-1. This projection can be carried out using theF-spin formalism. In the IBA-2 model, the lowest states are indeed fully symmetric, and using the calculations with the help of this projection, we explore the energy levels and the electric quadrupole transition probabilitiesB(E2; {ie393-01}) and γ-ray E2/M1 mixing ratios for selected transitions of^{162, 164, 166, 168, 170}Er. Owing to admixtures of non-fully-symmetric states in IBA-2, we renormalized the parameters (ε) and (κ). This is the first time we show that this projection can be applied to some heavier isotopes and the results obtained for^{162, 164, 166, 168, 170}Er isotopes are reasonably in good agreement with the previous experimental values.