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  • Author: M. Neumann x
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Abstract

Ill-designed regulation and inattentive supervision have contributed to the financial crisis, so has monetary policy. This article puts the focus on the European Central Bank (ECB). We test the hypothesis that the ECB’s change of concept in 2003 (money in the background) paved the way to follow the Fed’s overly expansionary monetary policy. We also discuss if policy should be geared to financial market stability. In contrast to the Greenspan-Bernanke-Mishkin view, some modest leaning against the bubble is supported. Finally, the ECB’s response to the crisis is evaluated. Cheap long-run jumbo loans and reduced security standards are potentially dangerous.

Abstract

Absorption of a pulse of laser light in the surface region of a solid causes a fast temperature increase, followed, after the end of the laser pulse, by a rapid decrease to the base temperature. Experiments with a Nd laser (power 105 - 106 W/cm2, half width of the pulse 150 μsec) showed that desorption of CO from a Pd surface reaches its maximum rate within the time constant of the system ( ~ 0.5 msec). This effect can be used for example to investigate the kinetics of adsorption /desorption processes by means of relaxation methods.

Abstract

By raising the inert gas pressure and thus changing the type of gas flow chemical transport processes in tubular halogen incandescent lamps may be influenced. At medium pressures in the region of laminar flow separation of halogen and inert gas due to thermodiffusion occurs, the halogen cycle breaks down, and bulb blackening of the lamp is observed. At low and high pressure, where the streaming behaviour of the gas phase is dominated by diffusion or turbulence, separation of halogen and inert gas is overcome and the lamps stay clean. Observed pressures for changing from laminar to turbulent flow are 3.5 atm in xenon, 5.5 atm in krypton, and > 8 atm in argon in good accord with the well-known Reynolds' criterion.

Abstract

The influence of thermodiffusion on bulb-blackening in tubular halogen incandescent lamps has been investigated experimentally for additions of methylenebromide, bromoforme or bromophosphornitrile to argon, krypton and xenon as filling gas. A strong dependence of blackening on the kind of the filling gas has been found. The influence of thermodiffusion on chemical transport may be interpreted in terms of the thermal diffusion coefficient a, which has been calculated according to Hirschfelder. Using higher concentrations of halogen, blackening of the bulb can be prevented, independent of the nature of the filling gas.

Aus der an hochgeglühten Wolframdrähten im elektrischen Potentialgradienten und im Temperaturgradienten auftretenden Oberflächenstrukturierung ergibt sich im Zusammenhang mit der elektrischen Überführung von Wolfram zur Kathode ein Thermotransport von Wolfram zum kälteren Probenteil. Die Transportwärme wird an Hand der Stufenstruktur sowie aus theoretischen Daten abgeschätzt.