Ozone in dairy chilling water systems: effect on metal materials

The use of pulsed ozone as a disinfecting agent in chilling water systems will be feasible only if components of the systems are not adversely affected. Pulsing ozone into water at room temperature for 20 minutes per day for 7 days caused greater weight loss of aluminium, carbon steel, copper, 304 stainless steel and 316 stainless steel samples than control samples; however, only weight loss for carbon steel was significantly greater (α= .05). Severe pitting was noted on ozone treated copper samples when observed by scanning electron microscopy. Black striations were observed on ozone treated carbon steel surfaces.     

EVALUATION OF A CARBOHYDRATE-BASED FAT REPLACER IN A FAT-REDUCED BAKING POWDER BISCUIT

Three selected carbohydrate-based fat replacers which were derived from pectin, gums, and oat bran (Slendid, Kel-Lite BK and TrimChoice-5, respectively) were used at a fixed rate in biscuits while shortening was reduced at 33, 66 and 100%. The principal effects of each fat substitute on biscuit quality varied with the fat substitute type and level of fat. Generally, fat substitute usage produced a significant (p < 0.05) increase in moisture content, as well as a light crust color. Variations in volume and crumb firmness were associated with the type of fat substitute and level of fat. Sensory data were found to be in agreement with the analytical data for moistness, crust color and crumb firmness. Crumb size decreased and bitterness was detected in biscuits as fat levels decreased regardless of the type of fat substitute.     

Structural and Functional Properties of Caseinate and Whey Protein Isolate as Affected by Temperature and pH

The structural properties, i.e., active sulfhydryl (SH), flexibility and hydrophobicity, and functional properties, i.e., solubility, emulsion activity (EA), emulsion stability (ES), foam overrun (FO) and foam stability (FS), of commercial sodium caseinate (SC) and whey protein isolate (WPI) solutions were investigated at pH 6, 7 and 8 and at 25, 55 and 65°C. WPI contained a higher concentration of active SH and was more hydrophobic than SC. WPI provided comparable solubility and EA, lower FO, but higher FS than SC. Temperature and pH effects on the two proteins were somewhat inconsistent.     

Using Quality Function Deployment to Select the Courses and Topics that Enhance Program Effectiveness

Decision science methods can be effective tools for enhancing organizational participation during strategic and complex decision processes. This involvement promotes development of group consensus for issues as difficult as relating organizational goals and the best methods to achieve them. In an academic context, such a process supports and enhances collegial participation. This paper describes an application of Quality Function Deployment (QFD) decision model to prioritize both courses and course content based on degree of impact on program objectives. The model was developed to quantify curricular decisions involved in restructuring a Masters of Engineering Management degree program. QFD supports selection of the courses and the curricular content that has the highest impact on program goals. The model provides a practical and quantitative methodology for developing faculty consensus in the selection of curricular topics based on a strategic program focus.     

High-Temperature Cermets: I, Compatibility

The stability of refractory oxides (Y₂O₃,-stabilized HfO₂ and ZrO₂, Tho₂, CeO₂), carbides (HfC, NbC, TaC, and ZrC), borides (NbB₂ and TaB₂), and HfN was determined in combination with the Groups VIA and VIIA refractory metals and combinations thereof. Thermodynamic calculations were made to predict stability up to 2500°K between the ceramic oxides and carbides in contact with Mo, Re, and W. Reaction studies were conducted between the ceramics and the Groups VIA and VIIA refractory metals in vacuum and in helium to 2750°C. The Mo-40 wt% Re, Re, and W were stable in contact with the carbides, nitrides, and oxides to 2450°C with two exceptions. These occurred when CeO₂ reacted with W at 1700°C and Mo-40 wt% Re reacted with WC. The Mo-40 wt% Re and Re also reacted with the NbB₂ and TaB_a above 2200°C to form very hard single-phase compounds.     

Precise Temperature Measurement in Debye-Scherrer Specimens at Elevated Temperatures

A general method was developed for precisely measuring the temperature of a Debye-Scherrer specimen at elevated temperatures. The method consists of measuring the lattice parameters versus temperature of a primary standard which forms one leg of a calibrated thermocouple, with both specimen and thermocouple junction in the X-ray beam, and then mixing the internal standard in powdered form with the powdered Debye-Scherrer specimen so that the lattice parameters of the internal standard directly indicate temperature. Gold was used as the primary standard, platinum as the other thermocouple leg, and magnesium oxide as the Debye-Scherrer specimen. The platinum/gold thermocouple was calibrated from 0° to 1000°C by the National Bureau of Standards. The lattice parameters (in angstroms; corrected for refraction in Ni Kα radiation) versus temperature are expressed by the equations: Gold (25° to 1000°C)

Magnesium oxide (25° to 932°C)

The temperature precision attained with the gold standard was estimated to be 1.5°C.     

Formation and Strength of Magnesia Whiskers

The formation of single-crystal magnesia whiskers during the compressive deformation of single crystals at room temperatures is described. These whiskers can have strengths of the order of millions of pounds per square inch. They are formed during fracture as a result of the discontinuous propagation of cracks which are mechanically relieving internal stresses resulting from plastic flow     

Activities in Li2O-, Na2O, and K2O-SiO2 Solutions

Activities of alkali metal oxides and silica are calculated for regions of the Li₂O-SiO₂, Na₂O-SiO₂, and K₂O-SiO₂ phase diagrams where volatility, cell potential, and thermodynamic data are available. For the high-silica composition regions, activities are calculated from the stable phase diagrams and assumptions based on sub-regular solution behavior. These data permit estimates of the phase boundaries for the metastable two-liquid regions in the Li₂O and Na₂O systems which may be compared with experiment. An estimate is also made of the critical point for K₂O-SiO₂ to determine whether metastable phase separation in this system will be experimentally obtainable.