Computed tomographic X-ray velocimetry for simultaneous 3D measurement of velocity and geometry in opaque vessels

Computed tomographic X-ray velocimetry has been developed for simultaneous three-dimensional measurement of flow and vessel geometry. The technique uses cross-correlation functions calculated from X-ray projection image pairs acquired at multiple viewing angles to tomographically reconstruct the flow through opaque objects with high resolution. The reconstruction is performed using an iterative, least squares approach. The simultaneous measurement of the object’s structure is performed with a limited projection tomography method. An extensive parametric study using Monte Carlo simulation reveals accurate measurements with as few as 3 projection angles, and a minimum required scan angle of only 30°. When using a single/source detector system, the technique is limited to measurement of periodic or steady flow fields; however, with the use of a multiple source/detector system, instantaneous measurement will be possible. Synchrotron experiments are conducted to demonstrate the simultaneous measurement of structure and flow in a complex geometry with strong three-dimensionality. The technique will find applications in biological flow measurement, and also in engineering applications where optical access is limited, such as in mineral processing.     

An Operations Research Approach to the Problem of the Sugarcane Selection

Selection for superior clones is the most important aspect of sugar cane improvement programs, and is a long and expensive process. While studies have investigated different components of selection independently, there has not been a whole system approach to improve the process. This study observes the problem as an integrated system, where if one parameter changes the state of the whole system changes. A computer based stochastic simulation model that accurately represents the selection was developed. This paper describes the simulation model, showing its accuracy as well as how a combination of dynamic programming and branch and bound can be applied to the model to optimise the selection system, giving a new application of these techniques. The model can be directly applied to any region targeted by sugarcane breeding programs or to other clonally propagated crops.     

Scheduling of road vehicles in sugarcane transport: A case study at an Australian sugar mill

Pressure to remain internationally competitive has forced Australian sugar mills to reduce capital and operational costs. Improved scheduling of road transport vehicles provides one such opportunity, as it would reduce vehicle queue and mill idle times and hence the number of vehicles needed. It is difficult for mill traffic officers to produce good transport schedules manually due to the need to service a large number of harvesters in different locations. To address this issue, research was undertaken participatively with a sugar milling company in Australia to produce and implement a mixed integer programming model that represents the road transport operations. Two meta-heuristics were applied to find a solution to the model, leading to potential cost savings of AU$240,000 per year versus schedules produced manually by the mill traffic officer. The model was also applied to explore regional planning options for a more integrated harvesting and transport system.     

Epimorphisms,dominions and semigroups

We investigate the preservation of epimorphism-related properties of semigroups under the taking of morphic images, of ideals and adjunction of an identity.Presented by Boris M. Schein.     

MRI of unilateral facial hypertrophy

Unilateral hypertrophy of facial muscles is an uncommon phenomenon with few reported cases in the worldwide literature. The few that have been reported have usually been associated with accompanying disease processes and clinical findings. In this paper, we describe a case of idiopathic hemihypertrophy of facial muscles and the MRI findings which were seen in this case.     

Kinetics of Ziegler propylene polymerization

Rate studies were done on the polymerization of propylene with the TiCl₃–diethyl aluminum chloride catalyst system. The polymerization is initially first-order with respect to propylene concentration. There is a rapid rate decline in the initial period, during which time the reaction becomes functionally second-order. A physical explanation for this behavior has been adapted from the Avrami equation for crystal growth kinetics. A yield equation was developed which fits experimental data closely. Rate correlations show that the initial rate is exponentially related to the TiCl₃/alkyl ratio. Water and other active hydrogen compounds reduce rate; hydrogen increases rate. A “bimetallic” mechanism is proposed which views catalyst activation as consisting of three equilibria, followed by a propagation step where an alkyl group is transferred to the growing chain, and a realkylation of the hydride that remains after the propagation step.     

Low resolution microwave spectra and indo calculations of phenylisothiocyanate and phenylisocyanate

The low resolution spectra of φNCS and φNCO have been studied in the microwave R-band region. The spectroscopic constant (B + C) has been evaluated for both molecules. These data have been used to obtain information on the orientation of the linear NCS and NCO group relative to the bond from the phenyl ring. The results indicate an opening of the φ-N-C angle over that found in the hydrogen counterparts HNCS and HNCO. A modified INDO calculation yields structural parameters which are consistent with the trends observed, and indicate that the opening of the angle in going from HNCS (HNCO) to φNCS (φNCO) can be attributed to delocalization with the phenyl ring.     

Development of Abraham model correlations for enthalpies of solvation of organic solutes dissolved in 1,3-dioxolane

Published excess enthalpy of mixing data has been assembled from the chemical literature for binary mixtures containing 1,3-dioxalane. The experimental data were converted into partial molar enthalpies of solution and enthalpies of solvation for solutes dissolved in 1,3-dioxolane using standard thermodynamic relationships. The compiled enthalpy of solvation data for 59 different organic solutes was used to derive mathematical correlations based on the Abraham solvation parameter model. The derived correlations describe the experimental enthalpy of solvation data in 1,3-dioxolane to within a standard deviation of 2.0 kJ mol^?1.     

Chemistry of thienopyridines. XXXIII. Synthetic routes to 5- and 7-substituted thieno[3,2-b]pyridines from the N-oxide

Thieno[3,2-b]pyridine ( 1 ) is oxidized to N-oxide 1a by means of m-chloroperoxybenzoic acid (83%). Compound 1a forms adducts with hydrogen chloride and picric acid and gives ring substitution alpha or gamma to the heteronitrogen atom. Thus, 1a plus nitric and sulfuric acids produces the 7-nitro-N-oxide 1m (63%), or plus phosphorus oxychloride gives a mixture of 5-chloro and 7-chloro ( 1j ) derivatives of 1 . Compound 1m is convertible into a variety of other derivatives of 1 , viz. 7-chloro-N-oxide, 1j , 7-bromo-N-oxide, 7-nitro and 7-amino. 5-Cyano- 1 , formed from 1a , is, in turn, transformed into a methyl imidate (93%), cyclic amidines, and a 5-tetrazolyl- 1 (91%). These results confirm the prediction that 1a , thieno[2,3-b]pyridine-4-oxide and quinoline 1-oxide should exhibit closely similar (i.e. analogous) chemical reactions.