A high statistics measurement of the Lambda(+)(c) lifetime

A high statistics measurement of the Lambda(+)(c) lifetime from the Fermilab fixed-target FOCUS photoproduction experiment is presented. We describe the analysis technique with particular attention to the determination of the systematic uncertainty. The measured value of 204.6 +/- 3.4 (stat) +/- 2.5 (syst) fs from 8034 +/- 122 Lambda(+)(c)-->pK(-)pi(+) decays represents a significant improvement over the present world average.     

Qualitative und quantitative Bestimmung von Acylneuramins?uren mit Hilfe der Capillars?ulen-Gas-Chromatographie

Ohne Zusammenfassung

---

Qualitative and quantitative determination of acylneuraminic acids by capillary gas-liquid chromatography

     

Transferability of some properties of localized molecular orbitals

The localized molecular orbitals of some related ten- and eighteen-electron systems have been studied. The transferability of the kinetic, self-interaction, Coulomb and exchange interaction energies on localized orbitals have been shown. The standard deviation of the kinetic and of the interaction energies (including exchange) are less than 2.5% except for lone pair orbitals of the oxygen atoms where the standard deviation is close to 4%.     

Quantum oscillatory phenomena in graphite intercalated with AsF5

Both Shubnikov-de Haas and de Haas-van Alphen oscillations are reported for C_8nAsF₅ (n=1,2, is the stage number). The observed oscillations are interpreted in terms of a tight-binding model for the band structure, and good agreement with both band parameters and effective carrier masses is found. In addition, the effective charge transfer per AsF₅ molecule (f=.37 for stage 1, =.41 for stage 2) is in basic agreement with previous determinations.     

High resolution NMR spectroscopy of heteroaromatic cations. II—pyrylium,thiapyrylium and seleninium cations

The barriers to internal rotation about the C? N bond in several thiopiperidides have been determined by the NMR technique. It was found that the barrier height (ΔG^?) increases in the series cinnamoylthiopiperidide<thiobenzoylpiperidide<phenylthioacetylpiperidide. This trend was discussed in terms of the electronic structure, using HMO calculations. For m-and p-substituted cinnamoylthiopiperidides the barriers were shown to increase with the electron withdrawing character of the substituent in the aromatic ring.