Optimization of mine layout for nuclear fuel assembly storage

The development of a mine layout for a nuclear waste repository in bedded salt is discussed. Optimizations of storage room arrangements and mine arrangements are addressed separately, and a conceptual repository design based on these optimizations is described.     

Protein reserves of ruminant animals: Nt‐methylhistidine as an index of myofibrillar protein turnover

Data on protein reserves in ruminant animals are limited. Protein reserves are utilized by high‐producing lactating dairy cattle during early lactation. Protein turnover within the body of an animal provides a mechanism for continuous redistribution of amino acids. Nitrogen balance studies have been used by researchers to investigate nitrogen utilization and protein reserves in ruminant animals. This method provides no information on where nitrogen is stored within the body or from which tissues nitrogen is mobilized. Urinary excretion of N^T‐methylhistidine appears to be a measure of myofibrillaf protein turnover, particularly in rats and humans. It has not been demonstrated that this method can be used as an index of myofibrillar protein turnover in ruminant animals.     

Opposite effects of met-enkephalin and leu-enkephalin on a discriminated shock-escape task.

Leu-enkephalin was found to impair and met-enkephalin to enhance acquisition of a discriminated Y-maze shock-escape task in Swiss-Webster mice at equivalent doses (100 μg/kg, ip). Naloxone (1 and 10 mg/kg) also enhanced acquisition of the escape response and blocked the impairing actions of leu-enkephalin. Neither naloxone nor the enkephalins influenced shock-induced locomotor activity in an open field. Results suggest that enkephalin actions on escape conditioning are mediated through opioid receptors. (43 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The measurement of demand for natural gas

This paper concentrates on the demand side of the natural gas markets. It discusses major issues influencing the penetration of natural gas in energy markets. First, a brief overview of the historical and future role of natural gas is presented. Next, the natural gas demand is discussed in conceptual terms. This is followed by projections of gas demand developed by the International Energy Agency, showing briefly the methodologies available and presenting an illustration of a method for projecting natural gas demand in Western Europe. Finally, the major factors that will influence natural gas penetration are assessed.     

Yellow Brick Road revisited.

Administered the Yellow Brick Road, a screening instrument for preschool children, to 504 children. Normative data were obtained using principal-components analysis. Results indicate that all subscales tapped a common factor. The auditory subscale appeared to be the best overall predictor. More normative data are needed regarding this 1st-grade readiness test. (1 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Particle Morphology of Amorphous Aluminum Hydroxycarbonate and Its Effect on Tablet Production

The particle morphology of amorphous aluminum hydroxycarbonate was studied by disaggregation induced by phosphate adsorption and direct observation by high resolution transmission electron microscopy. The primary particles are sheet-like and have equivalent diameters of 55A or less. The primary particles are believed to correspond to planar polymers comprised of six-membered rings of aluminum ions joined by double hydroxide bridges. Secondary particles form by attractive interaction of primary particles. The size of the primary particles affects the porosity of the secondary particles. The granulating and tableting properties of two spray dried amorphous aluminum hydroxycarbonates were shown to be related to the size of the primary particles and the porosity of the secondary particles.     

Surface charge characteristics of aluminum hydroxycarbonate as influenced by carbonate equilibrium

The isoelectric point of aluminum hydroxycarbonate suspension increases upon dilution with deionized water. The increase in the isoelectric point is directly related to the degree of dilution. Dilution with bicarbonate ion-containing solutions reduced the change in isoelectric point in comparison to dilution with deionized water. The change in isoelectric point was inversely related to the concentration of bicarbonate ion in the diluting solution. The increase in isoelectric point observed following dilution with deionized water was reversed by the addition of bicarbonate ion. The observations suggest that carbonate ions occupying potential determining sites in the primary particles are in equilibrium with carbonate/bicarbonate ions in solution. Formulation or processing factors which affect the equilibrium will affect the isoelectric point of aluminum hydroxycarbonate suspensions and will influence their physical properties.     

Lead Zirconate Titanate Hollow-Sphere Transducers

Millimeter-sized, hollow spheres of lead zirconate titanate were fabricated by blowing gas through a fine-grained slurry of PZT-5. After they were sintered, the spheres were poled in two ways: radially between inside and outside electrodes, and tangentially between two outside electrodes. The capacitance and vibration modes were modeled and measured for these two poling configurations. The two principal modes of vibration were a breathing mode near 700 kHz and a wall thickness mode near 10 MHz. These spheres have potential uses in medical ultrasound, nondestructive testing, and low-density transducer arrays.     

Uncoupling thermal problems of terminal storage of spent nuclear fuel assemblies in bedded salt

Spent nuclear fuel assemblies stored in bedded salt can be modeled with a large array of dimensioned decay heat sources (spent fuel assemblies) in an extended thermal conducting media. Although a finite-difference or finite-element representation of the total storage facility could be established, regions of the repository should be analyzed separately since a model of the total repository would require formidable digital computing capacity. This paper explains the basis for thermally analyzing the total storage facility with separate models for the stored fuel assembly package and the salt medium. In addition, the effect of fuel assembly packaging on the maximum fuel temperature, the related problems of fuel handling prior to storage, and uncoupling of the effects of mine ventilation and conduction in the salt medium are discussed.