Nowhere monotone functions and functions of nonmonotonic type

We investigate the relationships between the notions of a continuous function being monotone on no interval, monotone at no point, of monotonic type on no interval, and of monotonic type at no point. In particular, we characterize the set of all points at which a function that has one of the weaker properties fails to have one of the stronger properties. A theorem of Garg about level sets of continuous, nowhere monotone functions is strengthened by placing control on the location in the domain where the level sets are large. It is shown that every continuous function that is of monotonic type on no interval has large intersection with every function in some second category set in each of the spaces , and .

     

On-line DLTS investigations of vacancy related defects in low-temperature electron irradiated, boron-doped Si

Vacancy-related defects in Si are explored with deep level transient spectroscopy (DLTS). The measurements are performed on-line on irradiated p-type Si and a new trap with the signature (E_pa, _pa) = (0.18 eV, 6.5×10^-15 cm²) – only present at cryogenic temperatures – is studied. Furthermore, the bi-stable boron-vacancy complex is studied and its configuration at low temperatures is investigated and found to have the signature (E_pa, _pa) = (0.11 eV, 8.2×10^-15 cm²). PACS 71.55.Cn; 61.80.Fe; 61.82.Fk; 61.72.Ji     

Multiple release layer study of the intrinsic lateral etch rate of the epitaxial lift-off process

The lateral etch rate of AlGaAs in HF in the Epitaxial Lift-Off (ELO) process consists of two parts, an intrinsic and a radius-induced part. The intrinsic part is studied with a new approach in which multiple release layers are introduced in one sample. By letting an essential ELO process parameter vary over the different release layers, this parameter is examined, using only samples from one wafer. In this study, the influence of thickness, aluminium fraction, and doping concentration of the release layer on the lateral etch rate is investigated. For release layers with thicknesses below 10 nm, a positive correlation between thickness and intrinsic etch rate is found. Thicker release layers do not result in higher etch rates. Increasing aluminium fractions in the Al_xGa_1-xAs release layers result in higher etch rates. For aluminium fractions between 0.3 and 1, this effect covers almost six orders of magnitude. From the width of the V-shaped etch slits in samples that have been etched for 12 hours or more, the selectivity, i.e., the ratio of the etch rate of Al_xGa_1-xAs to GaAs, is determined. Selectivities between 4.3 and 8.6×10⁵ are found for x=0.3 and x=1, respectively. A variation in silicon doping is found to have no effect on the lateral etch rate, while increased zinc doping raises the etch rate significantly. PACS 81.05.Ea; 68.37.Hk; 81.15.Gh     

Preparation of a novel diphosphine-palladium macrocyclic complex possessing a molecular recognition site. Oxidative addition studies

A disphosphine-palladium(0) complex capable of recognising barbiturates has been prepared. Oxidative addition studies with a barbitiurate:aryl iodide conjugate provided new Pd(ii) complexes where the positioning of the Pd-bound aryl group is controlled by the molecular recognition event.     

Hesseltin A, a novel antiviral metabolite from Penicillium hesseltinei

[structure: see text] Hesseltin A 1, a novel compound of mixed polyketide-terpenoid origins was isolated from the filamentous fungus Penicillium hesseltinei. The structure and stereochemistry were determined from extensive one- and two-dimensional NMR and mass spectral data.     

Three dimensional alignment of molecules using elliptically polarized laser fields

We demonstrate, theoretically and experimentally, that an intense, elliptically polarized, nonresonant laser field can simultaneously force all three axes of a molecule to align along given axes fixed in space, thus inhibiting the free rotation in all three Euler angles. Theoretically, the effect is illustrated through time dependent quantum mechanical calculations. Experimentally, 3, 4-dibromothiophene molecules are aligned with a nanosecond laser pulse. The alignment is probed by 2D ion imaging of the fragments from a 20 fs laser pulse induced Coulomb explosion.