Corrosion of Cermet Anodes During Low Temperature Electrolysis of Alumina: Final Report

Successful development of inert anodes to replace carbon anodes in Hall cells has the potential benefits of lower energy consumption,lower operating costs, and reduced CO{sub 2} and CO emissions. Using inert anodes at reduced current density and reduced operating temperature (800 C) has potential for decreasing the corrosion rate of inert anodes. It may also permit the use of new materials for containment and insulation. This report describes the fabrication characteristics and the corrosion performance of 5324-17% Cu Cermet anodes in 100 hour tests. Although some good results were achieved, the corrosion rate at low temperature (800 C) is varied and not significantly lower than typical results at high temperature ({approximately} 960 C). This report also describes several attempts at 200 hour tests, with one anode achieving 177 hours of continuous operation and another achieving a total of 235 hours but requiring three separate tests of the same anode. The longest run did show a lower wear rate in the last test; but a high resistance layer developed on the anode surface and forced an unacceptably low current density. It is recommended that intermediate temperatures be explored as a more optimal environment for inert anodes. Other electrolyte chemistries and anode compositions (especially high conductivity anodes) should be considered to alleviate problems associated with lower temperature operation

Serious adverse events in patients with idiopathic pulmonary fibrosis in the placebo arms of 6 clinical trials

Background: Idiopathic pulmonary fibrosis (IPF) is a fatal interstitial lung disease characterized by irreversible loss of lung function and an unpredictable course of disease progression. Methods: The safety data for patients with IPF who received placebo in 6 clinical trials were pooled to examine the categories and frequencies of serious adverse events (SAEs) in this population. Results: In 1082 patients with IPF who received placebo, 673 SAEs were reported. Of these, 93 SAEs resulted in death (8.6% of patients). Respiratory-related conditions were the most frequently reported SAE (225 events, 16.33 per 100 patient-exposure years [PEY]), followed by infections and infestations (136 events, 9.87 per 100 PEY) and cardiac disorders (79 events, 5.73 per 100 PEY); these categories also had the most fatal outcomes (60, 10, and 10 deaths, respectively). The most frequently reported fatal respiratoryrelated SAEs were IPF and respiratory failure (38 and 11 patients, respectively), and the most frequently reported fatal infections and infestations and cardiac disorders were pneumonia (5 patients) and myocardial infarct

Thin-shell wormholes from black holes with dilaton and monopole fields

We provide a new type of thin-shell wormhole from the black holes with dilaton and monopole fields. The dilaton and monopole that built the black holes may supply fuel to construct the wormholes. Several characteristics of this thin-shell wormhole have been discussed. Finally, we discuss the stability of the thin-shell wormholes with a "phantom-like" equation of state for the exotic matter at the throat.Comment: 6 pages and 3 figures, some typos are corrected and accepted in Int.J.Theor.Phy

Divisive Gain Modulation with Dynamic Stimuli in Integrate-and-Fire Neurons

The modulation of the sensitivity, or gain, of neural responses to input is an important component of neural computation. It has been shown that divisive gain modulation of neural responses can result from a stochastic shunting from balanced (mixed excitation and inhibition) background activity. This gain control scheme was developed and explored with static inputs, where the membrane and spike train statistics were stationary in time. However, input statistics, such as the firing rates of pre-synaptic neurons, are often dynamic, varying on timescales comparable to typical membrane time constants. Using a population density approach for integrate-and-fire neurons with dynamic and temporally rich inputs, we find that the same fluctuation-induced divisive gain modulation is operative for dynamic inputs driving nonequilibrium responses. Moreover, the degree of divisive scaling of the dynamic response is quantitatively the same as the steady-state responses—thus, gain modulation via balanced conductance fluctuations generalizes in a straight-forward way to a dynamic setting

Selected ground-water data for Yucca Mountain region, southern Nevada and eastern California, through December 1996

The US Geological Survey, in support of the US Department of Energy, Yucca Mountain Site Characterization Project, collects, compiles, and summarizes hydrologic data in the Yucca Mountain region. The data are collected to allow assessments of ground-water resources during studies to determine the potential suitability of Yucca Mountain for storing high-level nuclear waste. Data on ground-water levels at 36 sites, ground-water discharge at 6 sites, and ground-water withdrawals within Crater Flat, Jackass Flats, Mercury Valley, and the Amargosa Desert are presented for calendar year 1996. Data collected prior to 1996 are graphically presented and data collected by other agencies (or as part of other programs) are included to further indicate variations of ground-water levels, discharges, and withdrawals through time. A statistical summary of ground-water levels at seven wells in Jackass Flats is presented to indicate potential effects of ground-water withdrawals in support of US Department of Energy activities near Yucca Mountain. The statistical summary includes the number of measurements, the maximum, minimum, and median water-level altitudes, and the average deviation of measured water-level altitudes for selected baseline periods and for calendar years 1992--96. At two water-supply wells and a nearby observation well, median water levels for calendar year 1996 were slightly lower (0.3 to 0.4 foot) than for the respective baseline periods. At four other wells in Jackass Flats, median water levels for 1996 were unchanged, slightly lower (0.2 foot), and slightly higher (0.2 and 0.7 foot) than for the respective baseline periods

Comparative Performance Evaluation of TCP variants on Satellite Environments

Satellite communications are essential to provide Internet access to wide areas, helping bridge the \u201cdigital divide\u201d. However, long RTTs and the possible presence of losses due to satellite channel errors, severely impair standard TCP performance. To overcome this problem several approaches are possible, including the adoption of enhanced versions of TCP. This paper focuses on these, by presenting the results of a comparative performance evaluation carried out in a satellite environment through a Linux testbed. The interest of the analysis lies in the wide variety of TCP variants considered and in the different aspects analyzed, such as performance at start-up, level of RTT unfairness and robustness against link losses. The results are analyzed at length in the paper and give interesting indications about the performance achievable on satellite channels by the most promising TCP variants proposed in recent years

PEPsal: a Performance Enhancing Proxy designed for TCP satellite connections

Internet communications with paths that include satellite link face some peculiar challenges, due to the presence of a long propagation wireless channel. In this paper, we propose a Performance Enhancing Proxy (PEP) solution, called PEPsal, which is, to the best of the authors' knowledge, the first open source TCP splitting solution for the GNU/Linux operating systems. PEPsal improves the performance of a TCP connection over a satellite channel making use of the TCP Hybla, a TCP enhancement for satellite networks developed by the authors. The objective of the paper is to present and evaluate the PEPsal architecture, by comparing it with end to end TCP variants (NewReno, SACK, Hybla), considering both performance and reliability issues. Performance is evaluated by making use of a testbed set up at the University of Bologna, to study advanced transport protocols and architectures for internet satellite communications