A NEW PROCEDURE FOR THE ACCURATE INDOOR MEASUREMENT OF SOLAR-CELL I-V CHARACTERISTICS

The present work describes and validates a method for the adjustment of light intensity in indoor solar-cell I-V tests. The procedure basically consists of the evaluation of the spectral-mismatch parameter as a function of light intensity before measuring. The simulator is set to the irradiance that produces a spectral-mismatch parameter equal to unity (or to some other desired value) and only then is the I-V curve taken. The main advantages are: no need to use very similar reference and test cells, direct extraction of the right whole I-V curve without cell models and ease to measure under different light intensities.     

EFFECT OF MICROBIAL ADSORPTION AT THE GAS/LIQUID INTERFACE ON OXYGEN ENHANCEMENT FACTORS

The adsorption of micro-organisms at the gas/liquid interface causes both an increase in the oxygen respiration rate and a decrease in the oxygen diffusion coefficient near the interface. An increase in the oxygen consumption rate increases the oxygen mass transfer rate into the bacterial broth but a decreased oxygen diffusion coefficient reduces the mass transfer rate. These two factors must be taken into account when enhancement factors are calculated.     

TERNARY EXTRACTION MODELING USING THE REDLICH-KISTER EXPANSION

Mathematical models for liquid-liquid extraction processes are not widely available. The correlation of liquid-liquid equilibrium for such a model is often difficult. One correlation, based upon the Redlich-Kister expansion for the molar excess Gibb's free energy, has been shown to accurately represent ternary liquid-liquid equilibrium systems used in liquid-liquid extraction operations.

The use of this correlation in an extraction model was investigated and found to be suitable for a ternary liquid-liquid extraction model with only minor limitations. A successful ternary liquid-liquid extraction model was developed using this equilibrium correlation.     

SURVEY OF STUDENT THERAPISTS' ATTITUDES TOWARD PSYCHODIAGNOSTIC REPORTS.

PRESENTS THE RESULTS OF A SURVEY QUESTIONNAIRE GIVEN TO 25 CLINICAL PSYCHOLOGY STUDENTS CONCERNING THE PSYCHOLOGICAL TEST REPORTS SUBMITTED ON PATIENTS UNDER THEIR CARE. RATINGS OF VALUE OF SPECIFIC REPORTS APPEARED TO BE A FUNCTION OF GENERAL ATTITUDES TO DIAGNOSTICS, AND WERE IN GENERAL SO LOW, THAT THE UTILITY OF SUCH TESTING IS QUESTIONED. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of berry ripeness on concentration,qualitative composition and extractability of grape seed tannins

Background and Aims: The evolution of seed tannins in three grape varieties grown in the same vineyard was followed from preveraison to harvest, to determine their pattern of accumulation. Also, to elucidate whether the use of 70% acetone as extracting solvent overestimate what will occur during fermentation, seed tannins were extracted throughout the ripening period with a method that involved a 3 days extraction with aqueous 12.5% ethanol and the results compared with the acetone extraction method. Methods and Results: For both methods, the extracted tannins were analysed following acid‐catalysis in the presence of excess of phloroglucinol. Seed tannins reached a maximum around veraison and decreased towards maturity, the mean degree of polymerization (mDP) varying only slightly during the studied period. When tannins were extracted with 12.5% ethanol, their concentration was much higher during the first part of the maturation than using acetone but was significantly lower at harvest. Conclusions: The decrease in extractable seed tannins during ripening was observed with both solvents. The differences observed in the concentration of tannins with both solvents could be due to the histochemical changes occurring in seeds during maturation. Significance of the Study: The differences observed in tannin concentration with the two different methods may indicate that when pulp maturity is reached before seeds are ripe, the fermenting solution will extract more tannins than the acetone method. These results point to the importance of extraction methodology when monitoring seed maturity for the prediction of seed tannins in wine.