ATW neutronics design studies

The Accelerator Transmutation of Waste (ATW) concept has been proposed as a transuranics (TRU) (and long-lived fission product) incinerator for processing the 87,000 metric tonnes of Light Water Reactor (LWR) used fuel which will have been generated by the time the currently deployed fleet of commercial reactors in the US reach the end of their licensed lifetime. The ATW is proposed to separate the uranium from the transuranics and fission products in the LWR used fuel, to fission the transuranics, to send the LWR and ATW generated fission products to the geologic repository and to send the uranium to either a low level waste disposal site or to save it for future use. The heat liberated in fissioning the transuranics would be converted to electricity and sold to partially offset the cost of ATW construction and operations. Options for incineration of long-lived fission products are under evaluation.

A six-year science-based program of ATW trade and system studies was initiated in the US FY 2000 to achieve two main purposes: (1) “to evaluate ATW within the framework of nonproliferation, waste management, and economic considerations,” and (2) “to evaluate the efficacy of the numerous technical options for ATW system configuration.”

This paper summarizes the results from neutronics and thermal/hydraulics trade studies which were completed at Argonne National Laboratory during the first year of the program. Core designs were developed for Pb-Bi eutectic (LBE) cooled and Na cooled 840 MW_th fast spectrum transmuter designs employing recycle. Additionally, neutronics analyses were performed at Argonne for a He cooled 600 MW_th hybrid thermal and fast core design proposed by General Atomics Co. which runs critical for and subcritical for of its four year once-thru burn cycle.

The mass flows and the ultimate loss of transuranic isotopes to the waste stream per unit of heat generated during transmutation have been calculated on a consistent basis and are compared. (Long-lived fission product incineration has not been considered in the studies reported here.)     

Interaction between estradiol-17b and growth hormone in control of food intake in weanling rats.

Discusses previous studies indicating that estradiol reduces the food intake of adult female rats, while prepubertal females are refractory to its appetite-depressing action unless they have been hypophysectomized. In an experiment with 30 ovariectomized and hypophysectomized Sprague-Dawley female rats, treatment of weanlings with pituitary growth hormone restored the refractoriness of the neural feeding system to estradiol. It is suggested that growth hormone masks ventromedial hypothalamic restraint of food intake. Because estradiol affects eating by acting on the ventromedial hypothalamus, it is ineffective in young animals, which are highly responsive to growth hormone. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An investigation of six- to eleven-year-old children with allergic disorders.

Compared 6-11 yr. old children with and without allergic reactions on their intellectual ability, academic performance, social interaction patterns, medical history, TAT responses, and scores on a number of other psychological tests. Placement in the allergic sample was determined by a medical history provided by the parents of each child. The allergic sample included 199 boys and 172 girls, while the nonallergic sample consisted of 419 boys and 400 girls. Results indicate that Ss who did not exhibit allergic reactions were otherwise healthier and were rated as superior on a number of academic, social, and emotional adjustment dimensions. Results are related to studies of psychosomatic children. (19 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Subcortical-type dysfunction in a case of AIDS-related Complex (ARC).

Examined the cognitive functioning of a 27-yr-old bisexual Black male with ARC manifested as acquired immune deficiency syndrome (AIDS) dementia, using a memory scanning procedure. Although the S demonstrated normal memory scanning accuracy, psychomotor slowing and impaired information processing were revealed by a reaction time (RT) task. Findings suggest that an abnormally slow rate of central information processing may be one feature of dementia associated with subcortical pathology in AIDS. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The structure and spacing of intra-urban retailing: Austin,Texas

Summary An incomplete hierarchy of shopping centers has been identified for Austin, With consideration of the CBD and planned ribbon developments, a complete hierarchy might well be postulated. The depleted population of lowest level centers has been noted and shown to be not incompatible with the other findings.However, some systematic elements have been deduced from the spacing of these centers. With a map transformation, a greater regularity may be found than had been detected here. But the actual distribution has been explained in terms of uneven densities of opportunities since the hierarchical requirement of central place theory had already been fulfilled. Topological variance in such a map transformation as has been suggested may considerably complicate a solution which could adequately account for the distribution of such transport oriented service centers as shopping centers. Further research on this data with such reordered space, using entropic analysis and evaluating the information contained in several distributions under different transformations might prove interesting. More complete data on shopping centers, particularly opening dates, and for defunct centers, store types and closing dates would aid the evaluation of the validity of the deductions made here.Donald Wade Jones is a Graduate Student, Department of Geography, University of Chicago and was previously a Graduate Student in the Department of Geography, University of Texas, at Austin. Kingsley E. Haynes, is an Assistant Professor, Department of Geography and the Lyndon B. Johnson School of Public Affairs, University of Texas, Austin.The authors would like to thank Dr. M. Woldenberg, Harvard University for his careful comments and suggestions on an earlier version of this paper. Any errors, however, are the sole responsibility of the authors.     

Interactive effects of text-based and task-based importance on learning from text.

Examined, in 3 experiments, the interactive effects of text-based importance (i.e., intrinsically important information such as main ideas) and task-based importance (i.e., information made important by a task) on recall for text. Exp 1 indicated that information relevant to an encoding task was recalled better than was task-irrelevant information. Exp 2 revealed an interaction between text-based and task-based importance. Information that was relevant to a task was recalled well regardless of its text-based importance. Information that was not relevant was recalled better if it was of high text-based rather than of low text-based importance. Exp 3 indicated interactive effects at both encoding and retrieval. Readers used flexible, compensatory strategies that reflected a trade-off between text-based and task-based importance. The use of multiple strategies occurred spontaneously without specific experimenter-based instructions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Selected abstracts from the thirty-sixth annual meeting of the Scandinavian society for electron microscopy

This article reviews work on the temperature dependence of electron radiation damage in organic materials using the electron diffraction method to monitor the destruction of crystalline order. It is clear from work on crystalline 1-valine, polyethylene and paraffin that radiation resistance improves by a factor of about four when the temperature is lowered from room temperature to liquid nitrogen temperature. At lower temperatures there is no apparent improvement.     

Microprocessor Control of Offshore Enhanced Oil Recovery Project

The proportioning of natural gas liquids among six injection wells while controlling the corresponding gas necessary to maintain a specified liquid to gas ratio for each individual well is discussed. To accomplish this proportioning, the system selects a master well, controls both liquid and gas header pressure, and calculates corrected flow rates. In addition to these functions the microprocessor also prints on demand both instantaneous flow rates and cumulative volume injected for each well.     

Fire performance of external wall claddings under a performance-based building code

New Zealand Building Code Performance requirements relating to fire performance of external walls are considered and methods of evaluating the potential for vertical fire spread are discussed. Classifying external wall claddings on the basis of performance in the ‘combustibility’ test has proved overly restrictive where some external cladding materials are concerned. Performance criteria based on heat relase or ‘degree of combustibility’ are proposed and they seem to provide a better classification scheme for external wall cladding materials. Heat release test data for ten different external wall cladding materials are presented.     

The thiazide-sensitive Na-Cl cotransporter is an aldosterone-induced protein

Although the collecting duct is regarded as the primary site at which mineralocorticoids regulate renal sodium transport in the kidney, recent evidence points to the distal convoluted tubule as a possible site of mineralocorticoid action. To investigate whether mineralocorticoids regulate the expression of the thiazide-sensitive Na-Cl cotransporter (TSC), the chief apical sodium entry pathway of distal convoluted tubule cells, we prepared an affinity-purified, peptide-directed antibody to TSC. On immunoblots, the antibody recognized a prominent 165-kDa band in membrane fractions from the renal cortex but not from the renal medulla. Immunofluorescence immunocytochemistry showed TSC labeling only in distal convoluted tubule cells. Semiquantitative immunoblotting studies demonstrated a large increase in TSC expression in the renal cortex of rats on a low-NaCl diet (207 +/- 21% of control diet). Immunofluorescence localization in tissue sections confirmed the strong increase in TSC expression. Treatment of rats for 10 days with a continuous subcutaneous infusion of aldosterone also increased TSC expression (380 +/- 58% of controls). Furthermore, 7-day treatment of rats with an orally administered mineralocorticoid, fludrocortisone, increased TSC expression (656 +/- 114% of controls). We conclude that the distal convoluted tubule is an important site of action of the mineralocorticoid aldosterone, which strongly up-regulates the expression of TSC.