Error-free 10 Gbit/s transmission using individual Fabry-Perot modes of low-noise quantum-dot laser

A comb-generating laser suitable for DWDM application is demonstrated on the basis of a multimode quantum-dot laser. Bit error rate < 10^-13 at 10 Gbit/s external modulation was measured for 10 longitudinal modes owing to low (<0.3% over 0.001-10 GHz) relative intensity noise of each individual mode.     

Structure and internal-stress formation in VT20 titanium-alloy welded joints

Microstructure, texture, and microhardness and residual-stress distributions are studied in a VT20 alloy welded shell consisting of two coaxial nested components connected by a circular weld.     

Parameters and Technology for Fabricating PIK Reactor Fuel Elements

The construction of the fuel elements of a high-flux PIK research reactor is described. The technological tolerances in the process of fuel-element fabrication are presented. The basic geometric and mass parameters of several standard batches of fabricated fuel elements are determined experimentally. Statistical analysis of the experimental data shows that the deviations in the main parameters fall within the limits of the indicated technological tolerances and are described by a Gaussian distribution to a high degree of accuracy.     

Pulsed underwater corona discharges as a source of strong oxidants: *OH and H2O2.

Because of undesirable side effects of chemical methods pulsed underwater corona discharges are emerging as a potential future advanced oxidation process (AOP) for water disinfection. In pulsed corona discharges a discharge channel is created, which contains a non-thermal plasma with a low degree of ionisation and low electron densities, but with electron energies of up to 10 eV. It has been demonstrated that electrons with this energy can dissociate water and oxygen molecules and produce various reactive radicals (*OH, H*, O*, HO2*), molecular species (H2O2, H2, O2), ultraviolet radiation and shock waves. It is supposed that the combination of all effects leads to a very efficient killing of microorganisms. To understand this in detail and to improve the efficiency of the overall system there is the need to develop suitable diagnostic methods for the quantitative determination of the various oxidants produced during the discharge. In this paper we present preliminary experimental results obtained with different chemical probes for *OH radicals, and H2O2 produced by pulsed corona discharges.     

Monitoring, removal and risk assessment of cytostatic drugs in hospital wastewater.

Cytostatic agents are applied in cancer therapy and subsequently excreted into hospital wastewater. As these substances are known to be carcinogenic, mutagenic and toxic for reproduction, they should be removed from wastewater at their source of origin.In this study the fate and effects of the cancerostatic platinum compounds (CPC) cisplatin, carboplatin, oxaliplatin, 5-fluorouracil (5-FU) and the anthracyclines doxorubicin, daunorubicin and epirubicin were investigated in hospital wastewater. Wastewater from the in-patient treatment ward of a hospital in Vienna was collected and monitored for the occurrence of the selected drugs. A calculation model was established to spot the correlation between administered dosage and measured concentrations. To investigate the fate of the selected substances during wastewater treatment, the oncologic wastewater was treated in a pilot membrane bioreactor system (MBR) and in downstream advanced wastewater treatment processes (adsorption to activated carbon and UV-treatment). Genotoxic effects of the oncologic wastewater were assessed before and after wastewater treatment followed by a risk assessment.Monitoring concentrations of the selected cytostatics in the oncologic wastewater were in line with calculated concentrations. Due to different mechanisms (adsorption, biodegradation) in the MBR-system 5 - FU and the anthracyclines were removed < LOD, whereas CPC were removed by 60%. In parallel, genotoxic effects could be reduced significantly by the MBR-system. The risk for humans, the aquatic and terrestrial environment by hospital wastewater containing cytostatic drugs was classified as small in a preliminary risk assessment.     

Developing flow and heat transfer to power law fluids in square,trapezoidal and pentagonal ducts

A computational method has been developed successfully to predict the developing flow and heat transfer to a power law fluid flowing in square, trapezoidal and pentagonal cross-section straight ducts. The governing three-dimensional equations are parabolized axially. An orthogonal body-fitted coordinate system is employed to handle any arbitrary simply-connected channel geometry. The transformed equations are discretized and solved by line SOR technique. The computer code is capable of handling various boundary conditions and incorporates variable fluid properties and viscous dissipation. Typical results are presented to demonstrate the applicability of the code developed.     

Simultaneous mass and heat transfer under mixed convection along a vertical cone

Steady laminar binary mixed convection flow along a vertical circular cone under the combined buoyancy effects of thermal and species diffusion is studied analytically. The analysis is confined to mass diffusion processes with low concentration levels. In the analysis the surface of the cone is assumed to be at a uniform temperature and uniform concentration. Numerical results for the local Sherwood number, local Nusselt number and local friction factor are presented. Representative temperature, concentration and velocity profiles are also shown. The analysis covers the diffusion of common gases and vapours into air. Considerations are given to the situations where the buoyancy forces assist and oppose the forced convection flow for various possible combinations of the thermal and species diffusion processes.     

Cutaneous graft-versus-host disease

Graft-versus-host disease (GvHD) includes inflammatory and/or fibrosing manifestations that may arise at various times after transplantation of any organ containing lymphoid cells. For the dermatologist, the importance of GvHD is real and current. Indeed, because it has become easier to perform bone marrow transplantation (EMT), the indications of BMT have become broader, making follow-up of patients receiving grafts a widespread practice. Nonetheless, GvHD remains a frequent complication of BMT and its principal target organ is the skin. Furthermore, recent innovations, such as grafting of umbilical cord blood and the mobilization of peripheral blood progenitor cells, will be the source of new questions concerning the development of GvHD under these conditions. Finally, because of its analogies with other spontaneous idiopathic skin diseases, GvHD constitutes a model that may lead to a better understanding of the pathophysiological features of these diseases. In this review, the cutaneous aspects of GvHD are emphasized.