Anode bottom burnout shape and velocity field investigation in a high amperage electrolysis cell

Long term burnout shape of the anode bottom is believed to reflect the quasi-stationary liquid metal interface dome-shaped deformation. The shape profiles and their interplay affect the MHD stability, the velocity fields, set up of new anodes and electrical efficiency of the cell. Spent prebake anode bottom profiles were systematically measured at Rusal 309 kA cell to obtain the overall view of the liquid metal deformation. The magnetic field distribution and velocities of liquid metal flow were measured in order to obtain a more complete characterization of the cell. The results are compared to the modelling results using the specialised MHD-VALDIS software giving the insight to the cell dynamics

Memory effects on descent from nuclear fission barrier

Non-Markovian transport equations for nuclear large amplitude motion are derived from the collisional kinetic equation. The memory effects are caused by the Fermi surface distortions and depend on the relaxation time. It is shown that the nuclear collective motion and the nuclear fission are influenced strongly by the memory effects at the relaxation time $\tau \geq 5\cdot 10^{-23}{\rm s}$. In particular, the descent of the nucleus from the fission barrier is accompanied by characteristic shape oscillations. The eigenfrequency and the damping of the shape oscillations depend on the contribution of the memory integral in the equations of motion. The shape oscillations disappear at the short relaxation time regime at $\tau \to 0$, which corresponds to the usual Markovian motion in the presence of friction forces. We show that the elastic forces produced by the memory integral lead to a significant delay for the descent of the nucleus from the barrier. Numerical calculations for the nucleus $^{236}$U shows that due to the memory effect the saddle-to-scission time grows by a factor of about 3 with respect to the corresponding saddle-to-scission time obtained in liquid drop model calculations with friction forces.Comment: 22 pages, 8 figures, submitted to Phys. Rev.

Effect of wind speed on aerosol optical depth over remote oceans, based on data from the Maritime Aerosol Network

The Maritime Aerosol Network (MAN) has been collecting data over the oceans since November 2006. The MAN archive provides a valuable resource for aerosol studies in maritime environments. In the current paper we investigate correlations between ship-borne aerosol optical depth (AOD) and near-surface wind speed, either measured (onboard or from satellite) or modeled (NCEP). According to our analysis, wind speed influences columnar aerosol optical depth, although the slope of the linear regression between AOD and wind speed is not steep (~0.004–0.005), even for strong winds over 10 m s<sup>−1</sup>. The relationships show significant scatter (correlation coefficients typically in the range 0.3–0.5); the majority of this scatter can be explained by the uncertainty on the input data. The various wind speed sources considered yield similar patterns. Results are in good agreement with the majority of previously published relationships between surface wind speed and ship-based or satellite-based AOD measurements. The basic relationships are similar for all the wind speed sources considered; however, the gradient of the relationship varies by around a factor of two depending on the wind data used

Maritime Aerosol Network as a Component of AERONET - First Results and Comparison with Global Aerosol Models and Satellite Retrievals

The Maritime Aerosol Network (MAN) has been collecting data over the oceans since November 2006. Over 80 cruises were completed through early 2010 with deployments continuing. Measurement areas included various parts of the Atlantic Ocean, the Northern and Southern Pacific Ocean, the South Indian Ocean, the Southern Ocean, the Arctic Ocean and inland seas. MAN deploys Microtops handheld sunphotometers and utilizes a calibration procedure and data processing traceable to AERONET. Data collection included areas that previously had no aerosol optical depth (AOD) coverage at all, particularly vast areas of the Southern Ocean. The MAN data archive provides a valuable resource for aerosol studies in maritime environments. In the current paper we present results of AOD measurements over the oceans, and make a comparison with satellite AOD retrievals and model simulations

Maritime Aerosol Network as a Component of AERONET - Relevance to Ocean Color Remote Sensing

The poster presents the current status of the Maritime Aerosol Network (MAN) as a component of AERONET. The MAN started collecting aerosol optical data in various regions of the World Ocean in November 2006 and has completed over 70 cruises, with many cruises ongoing and planned. The aerosol optical depth data collection will provide the international scientific community with the much needed data for the satellite retrieval validation, atmospheric correction and other applications. A public domain web-based archive is essential in the fundamental scientific aspect of aerosol optical studies over the oceans.JRC.DDG.H.3-Global environement monitorin