Investigators are studying hydrogen purification by membrane technology as a means to make the coal-to-hydrogen route economically attractive. To allow prediction of membrane performance and to facilitate comparisons between membrane and other technologies (cryogenic distillation, pressure swing adsorption), they developed a mathematical model to describe the permeation process inside a membrane module. The results of this model were compared with available experimental data (separation of CO{sub 2}/O{sub 2}/N{sub 2} mixtures). The model was first used to calculate the gas permeabilities from one set of mixed-gas experiments; the resulting permeabilities were then used to predict the results of the other mixed-gas experiments. The agreement between these predictions and the experimental data was good. However, model predictions using gas permeabilities obtained in pure gas experiments did not agree with the mixed gas experimental data. This disagreement is believed to be due to plasticization of the membrane by contact with CO{sub 2}. These results indicate that data obtained from experiments with mixed-gas feeds are necessary to adequately predict membrane performance when CO{sub 2} is present. The performance of different system configurations, including one and two stages of membrane modules, was examined. The different configurations examined were single module (SM), single module with recycle …

The usefulness of sister chromatid exchange (SCE) induction as a measure of low-level radiation effect was examined in a benthic marine worm, Neanthes arenaceodentata. Larvae were exposed to /sup 60/Co radiation for 12 to 24 h at total doses ranging from 0.5 to 309 R and at dose rates from 0.04 to 13 R/h. Animals exposed at intermediate dose rates (0.5, 0.6, 1.25, 2.0, and 2.5 R/h) had SCE frequencies per chromosome about twice that of those receiving no radiation (controls), whereas those exposed at the higher dose rates (7.0 and 13 R/h) had SCE frequencies lower than the controls. Animals exposed at the lower dose rates (0.04 and 0.1 R/h) had lower SCE frequencies than those exposed at intermediate dose rates (and higher SCE frequencies than controls). The length of chromosome pair number one differed among metaphase spreads and was used as an index of chromosome condensation in a given metaphase. Because there is a possibility that chromosome morphology may affect the ability to resolve SCEs, morphology will be monitored in future studies. A preliminary experiment was performed to assess the effects of 2.2 and 11.5 R/h for 24 h on growth and development. Larvae observed at 6 and …

A proposal of using extrapolation algorithms as an analytical - numerical tool for the evaluation of the beam-beam effects in storage rings is formulated. These algorithms already known to experts of Applied Mathematics are described in some detail. Physical models for the beam-beam interaction effects on betatron motion and polarization of a test particle are discussed and put in such a form to allow the application of the extrapolation algorithms.

The potential environmental and socioeconomic impacts of the production of energy contained in hot dry rock (HDR) is surveyed here. In general, careful siting and timing and routine control measures should be adequate to prevent significant environmental harm; sites of particular ecological or visual and recreational value, however, may require more extensive (and more expensive) precautions such as using multiwell pads to reduce land disturbance and dry or wet and dry cooling towers to reduce or eliminate the consumptive use of water. The most important uncertainty among the environmental concerns is the seismic response of HDR formations to short-duration fluid injections at pressures above fracture thresholds; continued monitoring at HDR development sites is necessary. The direct socioeconomic impacts of HDR development should be relatively minor, owing to its capital-intensive nature. Of greater potential importance are the indirect jobs resulting from such development, which could cause significant demographic (and thus fiscal and social) impacts in sparsely populated regions. However, such indirect growth is not expected to begin until a large, stable HDR industry is established in a region, and thus its impacts are expected to be permanent rather than transient.

Investigators are studying hydrogen purification by membrane technology as a means to make the coal-to-hydrogen route economically attractive. To allow prediction of membrane performance and to facilitate comparisons between membrane and other technologies (cryogenic distillation, pressure swing adsorption), they developed a mathematical model to describe the permeation process inside a membrane module. The results of this model were compared with available experimental data (separation of CO{sub 2}/O{sub 2}/N{sub 2} mixtures). The model was first used to calculate the gas permeabilities from one set of mixed-gas experiments; the resulting permeabilities were then used to predict the results of the other mixed-gas experiments. The agreement between these predictions and the experimental data was good. However, model predictions using gas permeabilities obtained in pure gas experiments did not agree with the mixed gas experimental data. This disagreement is believed to be due to plasticization of the membrane by contact with CO{sub 2}. These results indicate that data obtained from experiments with mixed-gas feeds are necessary to adequately predict membrane performance when CO{sub 2} is present. The performance of different system configurations, including one and two stages of membrane modules, was examined. The different configurations examined were single module (SM), single module with recycle …

This report calculates the effect of the conductances of the pumping lines on the pumping speeds of the vacuum pumps being used to pump the inner vessel, and annular space, vacuum tight during the CC Cryostat testing. Effective pumping speeds were calculated for various values of pressure via the above stated formulas (see calculations). Conductances of valves, elbows, and tees were calculated with the help of ref. 1, and the volumes of the inner vessel and annular space were calculated wtth the aid of ref. 2. The major results of these calculations follow. The attached graphs show the effective pumping speed vs. pressure, as well as the pressure vs. pumpdown time for both the inner vessel pumpdown and the annular space pumpdown. Many intervals of pressure were chosen in order to give a complete picture of the effects on the pumping speed, and pumpdown time. An important rule of thumb is that the effective pumping speed be close to the intrinsic pump speed in the region of interest for the best efficiency. With an infinite conductance, these quantities become equal. In the case of the annular space pumpdown. the effective pumping speed is within approximately 15% of the intrinsic pump …

The tar-sand resources of the US have the potential to yield as much as 36 billion barrels (bbls) of oil. The tar-sand petroleum-extraction technologies now being considered for commercialization in the United States include both surface (above ground) systems and in situ (underground) procedures. The surface systems currently receiving the most attention include: (1) thermal decomposition processes (retorting); (2) suspension methods (solvent extraction); and (3) washing techniques (water separation). Underground bitumen extraction techniques now being field tested are: (1) in situ combustion; and (2) in situ steam-injection procedures. At this time, any commercial tar-sand facility in the US will have to comply with at least 7 major federal regulations in addition to state regulations; building, electrical, and fire codes; and petroleum-industry construction standards. Pollution-control methods needed by tar-sand technologies to comply with regulatory standards and to protect air, land, and water quality will probably be similar to those already proposed for commercial oil-shale systems. The costs of these systems could range from about $1.20 to $2.45 per barrel of oil produced. Estimates of potential pollution-emisson levels affecting land, air, and water were calculated from available data related to current surface and in situ tar-sand field experiments in the US. These …

This report provides (1) a description of the coverage, benefits, financing and administration of the Japanese health insurance plans; (2) a discussion of the way in which reimbursement levels for health care providers are determined; and (3) an analysis of the way in which the provision of health care system is organized in Japan.

In 1973 the U.S. Supreme Court held that the Constitution protects a woman's decision whether or not to terminate her pregnancy, Roe v. Wade, 410 U.S. 113, and that a State may not unduly burden the exercise of that fundamental right by regulations that prohibit or substantially limit access to the means of effectuating that decision, Doe v. Bolton, 410 U.S. 179. But rather than settling the issue, the Court's rulings have kindled heated debate and precipitated a variety of governmental actions at the national, State and local levels designed either to nullify the rulings or hinder their effectuation. This brief discusses this ongoing issue, including related legislation and judicial history.