Transport phenomena in electric smelting of nickel matte: Part II. Mathematical modeling

A three-dimensional mathematical model was developed to simulate the distributions of electrical potential, heat release, temperature, and velocity in the slag and matte in a six-in-line 36 MVA capacity furnace for smelting nickel calcine. From Part I of this series, it was found that there was a substantial electrical potential drop at the electrode surface, likely due to arcing through evolved carbon monoxide. The incorporation of this phenomenon into the model permitted accurate calculation of the current, power, and temperature distributions in the slag and matte. The slag was found to be thermally homogenized due to the evolved gas, and to a lesser extent by natural convection. In contrast, the matte was thermally stratified; this finding was attributed to poor momentum transfer across the slag/matte interface. Ninety percent of the electrical energy was used in smelting reactions in the calcine; to simulate the heat transfer from the slag to the calcine, a heat transfer coefficient was deduced from plant data. The implications of these findings for stable furnace operation are discussed.     

Magnetic thin-film magnetometers for magnetic-field measurement

Thin magnetic-film magnetometers used for magnetic-field measurement are reviewed and compared. A large variety of magnetic thin-film magnetometers have been constructed, and in some cases their properties are unique. A summary of thin-film magnetometers and their performance is provided.     

GFP is the way to glow: bioimaging of the plant endomembrane system

It is less than a decade that the green fluorescent protein (GFP) and its spectral variants have changed the approach to studying the dynamics of the plant secretory pathway. GFP technology has in fact shed new light on secretory events by allowing bioimaging in vivo right to the heart of a plant cell. This review highlights exciting discoveries and the most recent developments in the understanding of morphology and dynamics of the plant secretory pathway achieved with the application of fluorescent proteins.     

The impact of bubble dynamics on the flow in plumes of ladle water models

Bubbly plumes are widely encountered in metallurgical processes when gas is injected into liquid metals for refining purposes. Based on the experimental findings from a water model ladle, this phenomenon was simulated with a mathematical model, paying special attention to the dynamics of the bubbles in the plume. In the model, the liquid flow field is first calculated in an Eulerian frame with an estimated distribution of the void fraction. The trajectories of bubbles are then computed in a Lagrangian manner using the estimated flow field, experimentally measured information on bubble drag coefficients, lateral migration due to lateral lift forces, and variation in bubble size due to breakup. Turbulence in the two-phase zone is modeled with a modifiedk-ε model with extra source terms to account for the second phase. The computed void fraction and turbulent liquid flow field distributions are in good agreement with experimental measurements.     

Landsat sensor performance: history and current status

The current Thematic Mapper (TM) class of Landsat sensors began with Landsat-4, which was launched in 1982. This series continued with the nearly identical sensor on Landsat-5, launched in 1984. The final sensor in the series was the Landsat-7 Enhanced Thematic Mapper Plus (ETM+), which was carried into orbit in 1999. Varying degrees of effort have been devoted to the characterization of these instruments and data over the past 22 years. Extensive short-lived efforts early in the history, very limited efforts in the middle years, and now a systematic program for continuing characterization of all three systems are apparent. Currently, both the Landsat-5 TM and the Landsat-7 ETM+ are operational and providing data. Despite 20+ years of operation, the TM on Landsat-5 is fully functional, although downlinks for the data are limited. Landsat-7 ETM+ experienced a failure of its Scan Line Corrector mechanism in May 2003. Although there are gaps in the data coverage, the data remain of equivalent quality to prefailure data. Data products have been developed to fill these gaps using other ETM+ scenes.     

A water model and numerical study of the spout height in a gas-stirred vessel

The height and width of spouts in a water model of a gas-stirred ladle were measured photographically. The shapes were found to be Gaussian, and correlations were developed for the height and width. To mathematically model the free surface effects, a novel combined staggered-grid and volume-of-fluid computational code was developed. It was tested successfully against an established code in the “broken dam” validation test. The new free surface code was added to an existing code for a gasstirred plume to model the entire vessel. It was found that the code under-predicted the actual spout height. The model handled the momentum of the plume accurately, but did not account for the phenomena associated with the bubbles breaking the surface. The importance of these inter-related phenomena had not been appreciated previously.     

Some implications of structural collapse during freeze-drying using Erwinia caratovoraL-asparaginase as a model

When the enzyme Erwinia caratovora L -asparaginase was freeze-dried in mixtures of lactose and sodium chloride, biological activity and protein structure were preserved during drying. However, by altering the ratios of the excipients in the formulation it was possible to obtain products which were pharmaceutically acceptable or unacceptable as assessed by the criteria of dried cake appearance, moisture content or ease of reconstitution.     

The evidence supports Douglas Merritte as Little Albert.

Replies to the comments made by R. A. Powell (see record 2010-08987-015) and H.W. Reese (see record 2010-08987-016) on the authors' original article (see record 2009-18110-004). The authors' recent article summarized the results of a seven-year search to determine the identity and fate of “Little Albert.” Examinations of Watson’s scientific production, correspondence, and public documents suggested that an employee at the Harriet Lane Hospital was Albert’s mother. The child’s birth records and contact with the woman’s descendents led us to Douglas Merritte, the individual we believe to be Watson and Rayner’s (1920) famous participant. Powell (2010, this issue) and Reese (2010, this issue) brought forth considerations that they believe are contrary to our conclusion. We thank these authors for their interest in our work and the American Psychologist for allowing us to elaborate on and provide additional support for the thesis that Douglas was Little Albert. (PsycINFO Database Record (c) 2010 APA, all rights reserved)