The Influence of Alloy Composition and microstructure on the corrosion behaviour of Cu-Ni alloys in seawater

The aim of the study was to relate the general corrosion behaviour of CuNi 10-alloys in seawater with its iron content and microstructure. To that end the microstructure of four commercial alloys with various Fe-contents (1.20-1.78%) and there laboratory melted alloys with various Fe-contents (1.5-2.5%) were investigated in the as delivered state and after three different heat treatments. Samples of these alloys were exposed to flowing natural seawater. During exposure electrochemical measurements were performed. After exposure the weight loss was determined. Moreover, for a number of samples the corrosion products were analysed by means of electron microprobe analysis. Irrespective of the Fe-content, the presence of discontinuous precipitates in the laboratory melted alloys turned out to be detrimental with regard to general corrosion. To a less extent this also holds for alloys with high concentrations of continuous precipitates, as observed for iron contents of 2 and 2.5%. The precipitate free alloys as well as the ones containing low concentrations of continuous precipitates because of low Fe-concentrations (<1.5%Fe) do show a good corrosion behaviour. The corrosion behaviour of commercial CuNi 10 Fe in the as received condition was generally comparable with that of laboratory melted alloys with continuous precipitates. The corrosion rates of the former do not exceed those of the latter, which are very low for practical applications. Finally the corrosion behaviour of five laboratory melted CuNi5 alloys, containing up to 4% fe in solution, was investigated. It turned out that their reciprocal polarisation resistance in the steady state situation is lower than those for the CuNi 10 Fe alloys

Low level remote sensing: The Doppler Radar wind profiler

Mesoscale phenomena such as thunderstorm and sea breeze frontal circulations are being investigated using a 50 MHz Doppler wind profiler at the Kennedy Space Center. The profiler installation will begin October 1, 1988 and will be completed by February 17, 1989. The focus of current research and plans for next year include: examination of vertical velocities associated with local thunderstorm activity and sea breeze frontal circulations and compare the vertical velocities to conceptual mesoscale models; implementation of space-time conversion analysis techniques to blend profiler data with National Meteorological Center's model output and other wind data such as jimsphere, windsonde and rawinsonde for mesoscale analysis; development of suggestions for use of wind profiler data in mesoscale analysis and forecasting at Kennedy Space Center; and problems detection in the quality of the profiler data during this research project. Researchers will work closely with MSFC to identify and solve the data quality problems

The Boys of Beaver Meadow: A Homosexual Community at 1920s Dartmouth College

In this article about an organized group of homosexual students at all-male 1920s Dartmouth College — the boys of Beaver Meadow — Nicholas L. Syrett points to the possibility of a gay rural identity and community at the very time when most queer historiography has focused on urban space as the precondition for gay community. In looking at this group of students he examines the classed and racial makeup of its members, arguing that while they may well have lived in a rural space, the means by which they constituted their gay identity were predicated on the same classed (and implicitly raced) status that allowed others in major cities to claim similar identities. Finally, Syrett explores the significance of the boys’ membership in a college fraternity and their participation in Dartmouth’s theatre program, dwelling in particular on what both of these activities — read alongside their homosexuality — can tell us about 1920s ideals of masculinity at an all male-college. Drawing on archival documents from Dartmouth College, “The Boys of Beaver Meadow” contributes to a growing body of work that seeks to problematize the urban/homosexual connection and does so in a specifically historical context, in this case 1920s New England

Interpretation of combined wind profiler and aircraft-measured tropospheric winds and clear air turbulence

In the first experiment, it was found that wind profilers are far better suited for the detailed examination of jet stream structure than are weather balloons. The combination of good vertical resolution with not previously obtained temporal resolution reveals structural details not seen before. Development of probability-derived shear values appears possible. A good correlation between pilot reports of turbulence and wind shear was found. In the second experiment, hourly measurements of wind speed and direction obtained using two wind profiling Doppler radars during two prolonged jet stream occurrences over western Pennsylvania were analyzed. In particular, the time-variant characteristics of derived shear profiles were examined. Profiler data dropouts were studied in an attempt to determine possible reasons for the apparently reduced performance of profiling radar operating beneath a jet stream. Richardson number and wind shear statistics were examined along with pilot reports of turbulence in the vicinity of the profiler

O desenvolvimento de um sistema computacional de sumarização multidocumento com base em um método linguisticamente motivado

This paper presents the studies conducted in the area of Natural Language Processing, more specifically, in Automatic Multi-document Summarization. We describe the steps for the production of a computational prototype, based on a linguistically motivated method, for summarizing news texts in Portuguese.Este trabalho apresenta os estudos realizados na área de Processamento de Linguagem Natural, mais especificamente, em Sumarização Automática Multidocumento. São descritos os passos para a produção de um protótipo computacional, baseado em um método linguisticamente motivado, para a produção de sumários de notícias jornalísticas escritas em português.FAPESPICMCPró-reitoria de Pesquis