Search

Research is presented concerning random scheduling and the amount of redirection of tasks which can be made to non-specialists from specialists in a service system model. Methods of discerning random assignment probabilities are discussed.

Results demonstrate that progression of crystallization of colloidal Silicalite-1 with aqueous tetrapropylammonium in the open and closed systems can be monitored at defined composition and temperature. Data also indicate that the aggregation of molecules is mediated by the interaction potentials of the nanoslab planes carrying tetrapropylammonium cations.

X-ray scattering and gel permeation chromatography were used to study the formation of silicate particles when gradually introduced to tetraethyl orthosilicate in tetrapropylammonium hydroxide and tetrabutylammonium hydroxide solutions. Results from the x-ray scattering experiments suggest that the scattering intensity is proportional to the volume of the particles and that it reaches a maximum reading only for cubelike entities. Therefore, it has been assumed that silicon is present within all scattering entities.

Turner's syndrome causes lack of sexual development and short stature in some females and is the result of all or part of one of the two female X chromosomes being absent. A study of 80 females with Turner's syndrome, 25 with a paternally-derived X chromosome and 55 with a maternally-derived X chromosome show that those with paternally-derived X chromosomes have greater cognitive function and better social skills than those with maternally-derived X chromosomes. It is concluded that the paternal copy of the X chromosome contains a genetic locus for social cognition.

EPR and vis-near-IR spectroscopy are employed to analyze the influences of ligand and zeolite topology on Co(II) Schiff base chelate structure in faujasite type zeolites. Ligand change experiments reveal the difference between Schiff base complex formation in solution and in a zeolite cage. Intrazeolitic chelation is controlled by preorganization of a coordination sphere.

A generalized quasi-one-dimensional simulation scheme for free-piston shock tunnels yields good performance data. The scheme's test model is the T4 shock tunnel's free piston compression. The simulation divides the test model into individual components and formulates boundary conditions for component interactions. A time-stepping loop uses the boundary conditions to move the whole model through each time step.

Application of the allylation of toluene, benzene and anisole in mineral acid medium and in microporous solid acids formed part of an attempt to study the feasibility of attaining functional selectivity in electrophilic aromatic substitution reactions. The related preferential formation of allyl substituted aromatics over acid zeolites was analyzed. In cases where the reaction does not involve the formation of homogeneous acid, functional selectivity which is unattainable in homogenous phase is feasible over microporous phase.

A three-stage approximate Riemann solver for the computation of hypervelocity turbulent flows is presented. The solver consists of three stages that complements each other in the analysis of the flows' intermediate pressure and velocity. To evaluate its dependability, this formulation is employed in the experimental study of a sphere and a sharp cone subjected to high Mach number flows. Results indicate that the approximate Riemann solver is a powerful tool in the analysis of exterme flow conditions and is highly compatible with vector computers.

A mass-loss model based on fundamental boundary-layer theory helps in predicting shock tube test time and shock speed. A quasi-one-dimensional simulation code employs the model to design shock and expansion tubes. A study demonstrates that the model can provide accurate test time predictions for all turbulent flow shock tubes. The model uses a computationally less expensive method to provide design information. The formulations, however, do not provide as much information as two-dimensional viscous codes.