Experimental Search for μd 3He Fusion

The vast majority of muon catalyzed fusion research has been concerned with muonic molecules of hydrogen isotopes only, since the dynamics of higher-Z muonic atoms in general preclude the formation of molecular systems. In the specific case of hydrogen–helium mixtures, bound muonic molecular states can exist, and thus it is possible to search for the reaction μd ³He $$\xrightarrow{{\tilde \lambda f}}$$ μ+α(3.66 MeV)+p(14.64 MeV). Until recently, the theoretical predictions for the nuclear fusion rate in the μd ³He molecule, ${\tilde \lambda }$ _f , ranged over one order of magnitude, from 10⁵ to 10⁶ per second. An experimental upper limit has been measured for ${\tilde \lambda }$ _f in HD + ³He giving a value (<6×10⁴ s^?1 [1]). We report on the analysis of an experiment in D₂ + ³He which has shown a signal coming either from the muon catalyzed reaction, or from the fusion in flight of ³He's formed from dμd fusion.     

The study of prompt and delayed muon induced fission

The mean life times of negative muons bound to actinide nuclei have been measured by detecting the time difference between a stopped muon and the arrival of fragments from delayed fission after muon capture. The deduced capture ratesΛ _c are 1.392(4)·10⁷/s for²³⁷Np, 1.290(7)·10⁷/s for²⁴²Pu and 1.240(7)·10⁷/s for²⁴⁴Pu. The results are compared with published data for the fission and the neutron decay channels and for the electron decay of the bound muon. Including a former measurement ofΛ _c for²³⁹Pu, an isotopic dependence of the muon capture rates in the Pu isotopes is clearly observed.     

Nuclear charge radii of the carbon isotopes 12C, 13C and 14C

Muonic X-ray energies of the K-series of the carbon isotopes ¹³C and ¹⁴C have been determined relative to ¹²C. For the first time, muonic atom measurements using radioactive ¹⁴C have been performed. Model-independent equivalent nuclear charge radii R_k,α and their differences have been deduced. The R_k,α radii increase by 10(14) and 32(11) am respectively with the filling of the $\text{1}\text{p}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$ neutron Subshell. The results are compared with recent elastic electron scattering data. The former natural carbon data have been reanalysed using a new value for the nuclear polarization. In terms of the rms charge radius, we then obtain $\text{〈r}{}^2\text{〉}{}^{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 2.472(16)}\text{fm}$ for the ¹²C isotope.     

Quantitative Bestimmung des Halothan-Metaboliten Trifluoressigs?ure im Urin durch eine Kombination des Head-Space-Verfahrens mit der IR-Spektroskopie

Ohne ZusammenfassungFrau B. Andrees danken wir für die sorgfältige technische Mitarbeit.     

Novel bulky esters of cellulose

Novel bulky esters of cellulose were synthesized homogeneously, applying the solvent systems DMA/LiCl or DMSO/TBAF, by conversion of the biopolymer with aryl polyester dendrons. The carboxylic acid moieties were efficiently activated in situ with CDI or the acid chloride was applied. Cellulose esters with DS values of up to 0.7 were obtained. The functionalization pattern was analyzed by different NMR spectroscopic techniques indicating that not only position 6 (primary hydroxyl group) but also the secondary one at position 2 was included in the reaction.     

Superaxial Gauges

Supersymmetric gauge theories can be suitably quantized in non-supersymmetric “superaxial” gauges without abolishing the basic advantages of the superfield technique. In this review the state of the art is presented. It includes the proof of renormalization and the proof of gauge independence and supersymmetry of observable physical quantities.     

Contributions to the Characterization of Chlorinated Polyisoprene Surfaces

Summary: The present work is focused on the characterization of the surface properties and the mechanical properties of chlorinated polyisoprene films. Cross-linked polyisoprene films were treated with acidified hypochlorite solution and the influence of the chlorination time on the surface properties was determined by spectroscopic techniques including FT-IR spectroscopy and X-ray photoelectron spectroscopy (XPS). The surface morphology was investigated by scanning electron microscopy (SEM), optical microscopy and contact angle measurements. In addition, the effect of the chlorination time on the tensile strength and ageing stability of natural rubber latex gloves was investigated.