Viscosity-Drift Technique for Determination of Critical Liquid-Liquid Immiscibility Temperature of Glasses

The time dependence of the low-temperature viscosity was used to determine the occurrence of phase separation in glass systems and to measure the critical immiscibility temperature. The technique is fast and easily performed and can be applied to materials with very low immiscibility gaps. Immiscibility temperatures for several technically important glass compositions are given.     

CONCENTRATION of ORANGE JUICE BY REVERSE OSMOSIS

Orange juice was concentrated by RO up to 50% hydraulic recovery with a polyamide membrane. Permeate fluxes and solute recoveries were determined at transmembrane pressures of 6.21 and 4.14 MPa. Pectinase treatment was required to prevent fouling and to allow Cleaning in Place procedures. Enzymatic treatment did not affect permeate flux or solute recoveries. Overall recovery of sugars, organic acids, and flavor-volatile components was approximately 93%.     

Viscosity and Density of Boron Trioxide

Extensive and accurate viscosity values for molten B₂O₃ are reported over the continuous range from 20 poises (at 1400°C) to 10¹⁰ poises (at 318°C). The measurements were made with a wide-range rotating-cylinder viscometer. The melts were pretreated by bubbling superdry nitrogen through them to ensure a minimum water content. Above 800°C the temperature dependence of the viscosity curve obeyed the Arrhenius equation; below 800°C the curvature was smooth showing no breaks. At the low temperatures, although its curvature decreased, the viscosity curve did not obey the Arrhenius equation. Densities were determined between 411° and 1400°C. Over this range the volume expansion coefficient changed by 1 order of magnitude from 3.35 × 10⁻⁴/°C to 3.34 × 10⁻⁵/°C. The liquid volume expansion coefficient above 1200°C was smaller than that of the glass below the glass transition temperature, indicating some type of structural rearrangement in B₂O₃.     

Comparative Study on Three Methods for Determining Air Content in Meat Batters

Measurement of air content in meat batters is useful, as larger amounts of air negatively affect some properties of comminuted products. Three methods were compared. One method (Vemag) involved liberation of entrapped air from the batter by the combined effects of vacuum and mechanical forces. The other two methods involved application of under- (Smrat) or over- (Handtmann) pressure and calculation of the air content using Boyle's ideal gas law. The Smrat showed the lowest reproducibility. However, being the most rapid and easy to use, it was the method of choice for routine quality and process control. The Vemag and more favorably the Handtmann were recommended for accurate and reproducible determinations.     

THE CHICAGO CONFERENCE ON CLINICAL TRAINING AND CLINICAL PSYCHOLOGY AT TEACHERS COLLEGE.

RESOLUTIONS OF THE CHICAGO CONFERENCE ON THE PROFESSIONAL PREPARATION OF CLINICAL PSYCHOLOGISTS WERE RESPONSES TO NUMEROUS SOURCES OF STRAIN WITHIN THE PROFESSION. THE VIABILITY OF THOSE RESOLUTIONS REQUIRES EMPIRICAL TESTING, AND AN ATTEMPT IS MADE TO ILLUSTRATE HOW ISSUES RAISED BY THE CONFERENCE HAVE BEEN DEALT WITH IN 1 DEPARTMENT. EXPERIENCE SUGGESTS THAT A GRADUATE PROFESSIONAL SCHOOL IS A FERTILE SETTING FOR IMPLEMENTING MANY OF THE RESOLUTIONS, BUT THAT THERE ARE DIFFICULTIES INVOLVED AS WELL. FURTHER PROPOSALS ARE SUGGESTED AS MEANS FOR RAISING THE PROBABILITY OF SUCCESSFUL IMPLEMENTATION OF THE CONFERENCE GUIDELINES. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dynamic Fracture Toughnesses of Reaction-Bonded Silicon Nitride

Dynamic fracture toughness specimens consisting of 5.1-mm thick, modified wedge-loaded, tapered double-cantilever-beam (WL-MTDCB) specimens, which are side-grooved on one side, were used to establish the room-temperature dynamic fracture toughness, K _ID vs crack velocity, a , relations of two reaction-bonded silicon nitrides. The measured dynamic crack extension histories were then used to drive a dynamic finite-element code in its generation mode which computes the dynamic stress intensity factors for a given crack extension. Results indicate that the K _ID vs a relations of reaction-bonded silicon nitrides do not follow the general trend in those relations of brittle polymer and steel. The slow initial crack velocity which was reported for glass was observed again in silicon nitride and resulted in a nonunique K _ID vs a relation, in contrast to the unique K _ID vs a material properties reported for brittle polymers and metals.     

Compositional mapping of bitumen using local electrostatic force interactions in atomic force microscopy

In recent years, many researchers have investigated bitumen surface morphology, especially the so‐called bee‐like structures, in an attempt to relate the chemical composition and molecular conformation to bitumen micromechanics and ultimately performance properties. Even though recent studies related surface morphology and its evolution to stiffness and stress localization, the complex chemical nature of bitumen and its time‐ and temperature‐dependent properties still engender significant questions about the nature and origin of the observed morphological features and how they evolve due to exposure to various environmental and loading conditions. One such question is whether the observed surface features are formed from wax or from the coprecipitation of wax and asphaltene. Our prior work was mainly theoretical; it used density functional theory and showed that the coprecipitation theory may not stand, mainly because wax–asphaltene interactions are not thermodynamically favourable compared to wax–wax interactions. This paper presents a comprehensive approach based on experiments to study surface morphology of bitumen and conduct compositional mapping to shed light on the origin of the bee‐like surface morphological features. We used Atomic Force Microscopy (AFM), with the main focus being on single‐pass detection and mapping of local electric properties, as a novel approach to enhance existing compositional mapping techniques. This method was found to be highly effective in differentiating various domains with respect to their polarity. The results of our study favour the hypothesis that the bee‐like features are mainly composed of wax, including a variety of alkanes.