ORIGINAL TITLE: INTERPRETATION OF MICROMIXING EFFECTS ON FAST CONSECUTIVE-COMPETITIVE REACTIONS IN SEMI-BATCH STIRRED TANKS BY A SIMPLE INTERACTION MODEL

Liquid-liquid equilibrium data for two ternary systems were obtained. The experimental data were measured for cyclohexane-toluene-sulfolane at 17, 25 and 50°C, and for hexane-toluene-sulfolane at 18 and 25°C. The NTRL and UNIQUAC models were used to correlate the experimental results and to calculate the phase compositions of the ternary systems. The agreement between the experimental results and the fitted values was equally good with both of the models.     

Seal-Inlet Disturbance Boundary Condition Correlations for Rotordynamics Models,Part 1: Correlation Development

Systematic parametric studies were performed to better understand seal-inlet rotordynamics. A CFD-perturbation model was employed to compute the seal-inlet flow disturbance quantities. Seal inlet disturbance boundary condition correlations were proposed from the computed seal-inlet quantities using the important parameters. It was found that the cosine component of the seal-inlet swirl velocity disturbance W _1C has a substantial impact on cross-coupled stiffness, and that the correlations for W _1C and W _1S should be used to replace the historical guess that seal inlet W _1C = 0 and W _1S = 0. Also, an extremely precise relationship was found between the cross-coupled stiffness and the seal-inlet swirl velocity (ω R _sh ?[Wbar] ₀ ). Thus, the number of experiments or computer runs needed to determine the effect of spin speed, shaft radius, and/or inlet swirl velocity on cross-coupled stiffness could be greatly reduced by plotting the simplified relationship of the cross-coupled stiffness against the swirl slip velocity. In addition, the upstream chamber size and shape were found to have a substantial influence on the seal-inlet swirl disturbance velocity W _1S which plays a significant role in determining the direct stiffness.     

Riboflavin Photosensitized Singlet Oxygen Oxidation of Vitamin D

Samples containing various levels of vitamin D and riboflavin, with and without ascorbic acid or a-tocopherol were prepared in a model system. Samples were stored in the light or in the dark at 45®C for up to 8 h. Headspace oxygen was determined by gas chromatography with thermal conductivity detection. Oxidation of vitamin D was not observed in samples without riboflavin stored in the light nor in samples with riboflavin stored in the dark. Vitamin D with riboflavin was oxidized under light. α-Tocopherol quenched singlet oxygen at a rate of 2.52 × 10⁸ M^-1 sec^-1, whereas ascorbic acid quenched singlet oxygen at a rate of 2.23 × 10⁷ M^-1 sec^-1.     

THE 7S PROTEIN FROM BRAZIL NUT1

The 7S (6.2S) protein of Brazil nut (Bertholletia excelsa) was isolated by ammonium sulfate solubilization from a high molecular weight fraction which contained primarily the major 11S (10.5S) nut globulin excelsin. Electrophoretic characterization of the protein showed that, in addition to sedimenting more slowly, it differed from excelsin in size, being smaller, and in subunit composition.     

THE EFFECTS OF TURGOR PRESSURE ON PUNCTURE AND VISCOELASTIC PROPERTIES OF TOMATO TISSUE

The effects of turgor pressure on puncture and viscoelastic properties of mature-green tomato pericarp were examined using tissue discs soaked in a range of osmotica (0.0–0.6 M mannitol) for at least 36 h at 4C. Turgor pressure was estimated from the osmotic potential of soaking solutions that induced incipient plasmolysis. Based on volume changes, the osmotic potential and turgor pressure of fresh tissue were estimated to be −0.56 ± 0.08 MPa and 0.20 MPa, respectively. However, puncture and viscoelastic properties corresponded to a turgor pressure of 0.15 MPa. The discrepancy between calculated and actual turgor pressures was attributed to the presence of apoplastic solutes. The data from this study revealed a general increase in cell wall stress, strain and elasticity with increasing turgor. With increases in turgor above that of untreated tissue both wall extensibility and elasticity became limiting and thus cell wall stiffness increased. Conversely, a decrease in turgor below that of untreated tissue led to an increase in viscoelasticity. Increases in bioyield and pseudoplastic bioyield strains with a variation in turgor from that of untreated tissue were consistent with cell debonding as a dominant mechanism of tomato tissue bioyielding. The reduced failure force, deformation and firmness with increasing turgor were consistent with cell rupture as a predominant mechanism of failure of mature-green tomato pericarp tissue.     

DOES INNER CITY PUBLIC HOUSING EXACERBATE THE EMPLOYMENT PROBLEMS OF ITS TENANTS?

ABSTRACT: This article analyzes whether inner city public housing exacerbates the employment problems of its tenants. Results from two evaluations of public housing demonstrations are used to test the potential impact of location, address discrimination, eligibility criteria, and rent schedules on tenant work behavior. To supplement this analysis, the effects of public housing on tenant employment, including self-employment, are estimated using a unique cross-sectional data set known as the Urban Poverty and Family Life Survey. The results do not support the claim that public housing, independent of tenant characteristics, contributes to employment patterns. While it is true that most public housing residents do not work, their counterparts in the private real estate market are no more likely to be employed or to have ever worked. Overall, these results indicate that the provision of public housing does not inhibit work behavior.     

ExperTAXsm: an expert system for corporate tax planing

Abstract: This paper describes the development of ExperTAX^sm, an expert system designed as a part of the service rendered by the audit and tax practices of the accounting firm of Coopers & Lybrand in the corporate tax accrual and planning function. The current operating environment is described and the expert system based solution is presented. The knowledge engineering process is described in detail and novel techniques for knowledge extraction are presented. The resulting system and its knowledge base is also presented together with a discussion on detailed knowledge acquisition and ongoing knowledge base maintenance facilities.