4,293 research outputs found
In-plane Magnetic Field Dependent Magnetoresistance of Gated Asymmetric Double Quantum Wells
We have investigated experimentally the magnetoresistance of strongly
asymmetric double-wells. The structures were prepared by inserting a thin
AlGaAs barrier into the GaAs buffer layer of a standard
modulation-doped GaAs/AlGaAs heterostructure. The resulting
double-well system consists of a nearly rectangular well and of a triangular
well coupled by tunneling through the thin barrier. With a proper choice of the
barrier parameters one can control the occupancy of the two wells and of the
two lowest (bonding and antibonding) subbands. The electron properties can be
further influenced by applying front- or back-gate voltage.Comment: 4 pages, 5 figures, elsart/PHYEAUTH macros; to be presented on the
EP2DS-15 Conference in Nara, Japan. Revised version. To appear in Physica
CO2 as moderator for biomass gasification
Biomass can be converted into gaseous fuel by high-temperature reactions with a gasifying agent. The gasifying agent consists, in most cases, of oxygen and of a moderator, which is usually water vapour. Here we show that waste CO2 can be used instead of, or together with, water vapour to moderate the process of biomass gasification in a catalytic fluidized bed of dolomitic limestone. Such use of CO2 increased substantially the carbon and energy conversion efficiency and decreased the amount of tars in the produced gas
An influence of static load on fatigue life of parts under combined stress
The paper deals with a special case of multiaxial fatigue in a plain stress possessing one component static and the other dynamic. Exponents of Haigs' limit curves were obtained experimentally both for tensile fatigue test and combined tensile/torgue tests. Errors of estimated fatigue lives are less than 20 %
- …