Estimating Solar Irradiance on Inclined Surfaces: A Review and Assessment of Methodologies

A variety of numerical models for calculating the solar irradiance for an inclined surface are described and evaluated using data for Vancouver, B.C., Canada. While all the hourly models have a common approach for calculating the direct component of the solar irradiance there is a variety of methods for calculating the diffuse irradiance based on the portion of the sky hemisphere within the field of view of the surface. A less significant distinction between the models is in the methods used to calculate the amount of radiation received as a result of reflection from adjacent surfaces.

The paper demonstrates that the principal features of the anisotropic distribution of sky radiance must be included in the numerical computations since the use of the unrealistic isotropic model leads to significant short and long term errors. Inclusion of directional reflectance in the slope irradiance calculations will lead to increased accuracy for the estimated values, with greatest improvement being achieved in the winter months due to a zenith angle dependency on the significance of the directional reflectance.

Errors in estimating the slope irradiance with an anisotropic model are shown to compare favourably with the errors associated with a direct measurement of the solar irradiance.     

CHANGES OF SUGAR PROFILES IN CANNED CLINGSTONE PEACHES

The effect of post-canning storage on sugar profiles in canned clingstone peaches (Primus persica var. ‘Halford’) sweetened with various combinations of sucrose, 62 D. E. corn syrup and 42% high fructose corn syrup was investigated. The sugars in the peach syrups were monitored at 1, 20 and 30° C after storage for 0, 6, 9 and 12 months. The individual sugars in the peach syrups were separated and analyzed by high pressure liquid chromatography (HPLC). Storage of the canned peaches at 30° C resulted in a rapid decrease in sucrose and a simultaneous increase in fructose and glucose. The hydrolysis of sucrose was successively slower at 20 and 1°C. It was observed that the sugar profiles were also dependent on the initial concentration of the sugar components, time of storage and acidity of the canned peaches. The concentration of maltose showed great fluctuation during storage. The rapid loss in quality acceptance of canned clingstone peaches at high storage temperature was explained by the changes in sugar profiles and the accompanying undesirable chemical and physical changes.     

The Role of Instrumental Colour Control in the Optimization of Dyehouse Performance

The paper describes the general techniques used and the results obtained in pilot plant and commercial dye-house experiments carried out to demonstrate the potential of an inhouse spectrophotometer and minicomputer system in:

• 1 high-accuracy recipe prediction to produce bulk dyehouse recipes without laboratory check dyeing
• 2 calculation of redye procedures to correct off-shade bulk dyeing
• 3 control of dyehouse pass/fail matching by instrumental methods
• 4 preparation of recipe cards, druglines and cost information by computer methods.

     

Calcium Alginate Films: Thermal Properties and Permeability to Sorbate and Ascorbate

Calcium alginate films were prepared by the pH-controlled release of calcium ions into alginate solution or by the cooling of hot calcium alginate gels. Thermogravimetry and calorimetry showed that the controlled Ca release films contained a greater amount of high-temperature component, and required extra energy to dissociate the tightly crosslinked calcium alginate. Structural differences were reflected by the permeability of the two films to potassium sorbate: 1.06 × 10^–7 (controlled Ca release) and 1.58 × 10^–7 cm²sec^–1 (cooled). Apparent activation energy was estimated to be for the diffusion of potassium sorbate 24.1 KJ·mol^–1, sodium ascorbate 23.7, and ascorbic acid 36.2. Results suggested that the pH of the diffusant solution had an interactive effect on the alginate film.     

DISCRIMINATED LEARNING AND REVERSAL IN THE WHEEL-TURN AVOIDANCE SITUATION.

2 STIMULI, ONLY 1 OF WHICH WAS PAIRED WITH SHOCK, WERE USED IN 2 EXPERIMENTS INVESTIGATING STIMULUS DISCRIMINATION AND REVERSAL EFFECTS IN AVOIDANCE LEARNING. THE FINDINGS INCLUDED: (1) NO DIFFERENCES IN LEARNING ATTRIBUTABLE TO THE STIMULUS (BUZZER OR TONE) THAT WAS PAIRED WITH SHOCK, (2) DISCRIMINATED RESPONDING SUCH THAT THERE WAS CONTINUED RESPONDING TO THE SHOCK-PAIRED STIMULUS AND REDUCED RESPONDING TO THE UNPAIRED STIMULUS, AND (3) DISCRIMINATED RESPONDING AFTER PAIRED AND UNPAIRED STIMULI REVERSALS BUT WITH GRADUALLY DETERIORATING DISCRIMINATION WITH SUCCESSIVE REVERSALS. (FRENCH SUMMARY) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Production of Extracellular β-Glucosidase and α-Galactosidase during Fungal Growth on Polygalacturonate

Filamentous fungi (Aspergillus oryzae, Scopulariopsis sp., and Penicillium brevicompactum) and yeast-like fungi (Aureobasidium pullulans) were induced to produce extracellular β-D-glucosidase (β-D-glucosidase glucohydrolase, EC 3.2.1.21) and α-D-galactosidase (α-D-galactoside galactohydrolase, EC 3.2.1.22) by polygalacturonate in the growth medium. These extracellular enzymes were not produced during growth of the microorganisms on cellobiose or melibiose.