OCEANIC METHANE HYDRATES: A "FRONTIER" GAS RESOURCE

Methane hydrates are ice-like compounds consisting of natural gas (mainly methane) and water, whose crystal structure effectively compresses the methane: each cubic metre of hydrate can yield over 150 cu.m of methane. Hydrates "cement" sediments and impart considerable mechanical strength; they fill porosity and restrict permeability. Both biogenic and thermogenic methane have been recovered from hydrates.
Hydrates occur in permafrost regions (including continental shelves), and are stable in ocean-floor sediments below water depths of about 400 m in the "Hydrate Stability Zone" (HSZ). This is a surface-parallel zone of thermodynamic equilibrium that extends down from the sediment surface to a depth determined by temperature, pressure and local heat flow. Methane and water are stable below the HSZ.
Although the economic recovery of hydrates has taken place in Arctic regions, oceanic hydrates offer far greater potential as an energy resource. A variety of traps for methane gas can be formed by oceanic hydrates. In addition to the gas within the hydrates themselves, simple gas traps in closures beneath the HSZ in the vicinity of bathymetric highs, and complex traps involving both hydrate and structural/stratigraphic components, have been observed.
It has been estimated that at least twice as much combustible carbon occurs associated with methane hydrates as in all other fossil fuels on Earth. The evaluation of methane in, and associated with, oceanic hydrates therefore constitutes a major energy exploration frontier.     

Developing a More Rapid Test to Assess Sulfate Resistance of Hydraulic Cements

External sulfate attack of concrete is a major problem that can appear in regions where concrete is exposed to soil or water containing sulfates, leading to softening and cracking of the concrete. Therefore, it is important that materials selection and proportioning of concrete in susceptible regions be carefully considered to resist sulfate attack. American Society for Testing Materials (ASTM) limits the tricalcium aluminate phase in cements when sulfate exposure is of concern. The hydration products of tricalcium aluminate react with the sulfates resulting in expansion and cracking. While ASTM standard tests are available to determine the susceptibility of cements to sulfate attack, these tests require at least 6 months and often up to a year to perform; a delay that hinders development of new cements. This paper presents a new method for testing cement resistance to sulfate attack that is three to five times faster than the current ASTM tests. Development of the procedure was based upon insights on the degradation process by petrographic examination of sulfate-exposed specimens over time. Also key to the development was the use of smaller samples and tighter environmental control.     

Cognitions and behavior in asymmetric social dilemmas: A comparison of two cultures.

This study investigated whether cognitions and behavior in an asymmetric social dilemma can be predicted by national culture. Results indicated that, as predicted, groups of decision makers from Japan--a collectivist, hierarchical culture--were more cooperative, expected others to be more cooperative, and were more likely to adopt an equal allocation distribution rule to resolve the dilemma than were groups of decision makers from the US--an individualist, egalitarian culture. An opportunity for communication had a greater impact on expectations of others' behavior in groups of U.S. decision makers than in groups of Japanese decision makers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dynamic fatigue experiments on optical fibers

Optical fibers should have a minimum life of 25 years. Proof testing is usually done in order to have only high-strength fibers and to evaluate their lifetimes. The behavior of the fibers is studied in terms of the mechanism of slow growth of microcracks. A maximum stress that will be allowed in the subsequent usage of the fiber is then calculated, performing extrapolations from measurements which last a few months to times which last more than 25 years. As might be expected, papers have been published that indicate this procedure leads to inaccurate predictions. Work reported here involves fibers with a broad distribution of strengths. These were used for the purpose of reducing test times. Dynamic fatigue tests were done under atmospheric and inert environments. Results were used to obtain portions of the universal fatigue curve in order to assess the potential accuracy of long-term extrapolation from high-strength fiber tests.     

Integration architecture of expert systems, neural networks, hypertext, and multimedia can provide competitive opportunities for industrial applications

This paper promotes the idea of integration of computer software technologies; such as, expert systems, neural networks, hypertext, multimedia, and graphics user interface (GUI), to an unique hybrid system that increase market opportunities and competitiveness. The goal is to present ingredients of a business strategy that can ensure the capability to provide long-term competitiveness for industrial applications. Concepts for development integration and flexibility, prototype system transferring, teaming, and other consideration for winning, evolving at The University of Tennessee Space Institute (UTSI) and the Center for Space and Applied Research (CSTAR), are presented to amplify on salient aspects of competitiveness.     

Visualization for climate modeling

Techniques for visualizing several climate variables, particularly clouds and wind velocities, are discussed. The techniques are volume rendering, textured contour surfaces, and vector field rendering. The application of these techniques is discussed in the context of a high-definition television (HDTV) animation produced to show global cloud motion during ten simulated days in January. The computational grid is defined by nearly a million grid points-320 evenly spaced longitudes, 160 unevenly spaced latitudes, and 19 unevenly spaced surfaces of constant geopotential. The climate variables at every grid point were output at every hour of simulated time, resulting in 380 MB of data per simulated day     

Bragg Reflection Band Stop Filter for ECE on Wega

Notch filters are required to protect sensitive millimeter wave diagnostics in fusion experiments from gyrotron stray radiation in the plasma vessel. A new type of notch filter based on a waveguide Bragg reflector is presented that can provide one or more defined stop bands in one standard waveguide frequency band.     

Asborin inhibits Aldo/Keto reductase 1A1

Asborin is the carbaborane analogue of aspirin. Replacement of the phenyl ring in aspirin by ortho‐carbaborane was found to change the pharmacological profile of the compound remarkably. Unlike aspirin, asborin cannot selectively acetylate a single serine residue in the active site of cyclooxygenase, and as a result inhibitory potency is reduced. Activation of the acetyl group and the presence of the hydrophobic and bulky cluster therefore did not meet the requirements for cyclooxygenase inhibition. Both features, however, match perfectly for inhibition of the aldo/keto reductase family. Herein, we describe the identification of aldo/keto reductase (AKR) 1A1 as an enzymatic target of asborin, which is inhibited in the low micromolar range. The detailed mode of inhibition was studied and is discussed with respect to the cluster properties. The results shed light on how ortho‐carbaborane can be used as a drug synthon, as well as on the development of carbaborane‐based inhibitors of other aldo/keto reductases.