Survival of rotavirus SA-11 on vegetables

Survival of rotavirus on lettuce, radishes, and carrots was studied to evaluate the potential of rotavirus transmission by vegetables irrigated with wastewater. The vegetables were contaminated with rotavirus SA-11 and stored at 4°C and room temperature in covered and uncovered containers to simulate post harvest conditions. Virus decay rates were greater on radishes and carrots than lettuce. Decay rates of rotavirus on lettuce, radish, and carrot ranged from ?0·057 to ?0·479 (log₁₀ pfu/day). Rotavirus SA-11 survived on lettuce, radish, and carrot for 25 to 30 days at 4°C but at room temperature survival was very different for the various vegetables varying from 5 to 25 days. Greatest survival was always observed on the lettuce. These data suggest that rotaviruses can survive long enough on contaminated vegetables as to be transmitted by this vehicle.     

Lithium/lithium vanadium oxide secondary batteries: IV. Evaluation of factors affecting the performance of test cells

With the aim of optimizing the performance of Li/Li_1+xV₃O₈ cells, several aspects of cathode preparation have been examined. The influence of synthesis technique, nature and amount of conductive additives, compacting pressure, cathode loading, and particle size, has been investigated. Furthermore, the role played by the solutions on cathode efficiency has been outlined. The formulations which perform best are based on small-sized particles blended with about 20% acetylene black and compacted at very high pressures to improve the contact between particles. Such cathodes can provide high capacities at high rates and good cycling efficiencies. The kinetic loss of capacity, observed during the first few cycles, may be alleviated by choosing solutions with high fluidity and conductivity.     

Upgrading coal-derived liquids to diesel fuel

Distilled fractions of a coal-derived liquid from the H-Coal process were upgraded to diesel fuel by catalytic hydrotreatment. The total hydrotreated products were distilled into naphtha (<180°C) and diesel fuel fractions (>180°C) and the diesel fractions were analysed for hydrocarbon-type composition, hydrogen content and some diesel fuel properties. GC—MS-analyses were carried out on the hydrocarbon-type fractions to identify individual chemical compounds. To investigate the effect of different distillation cut points on diesel fuel yield and properties, cut points for one hydrotreated product were varied. The diesel fuel cetane numbers were correlated with percentage hydrogen, total aromatics and saturates. Cetane numbers above 40 were obtained for diesel fuels containing (i) more than 75% saturates, (ii) less than 15% total aromatics and (iii) a hydrogen content above 12.8%. Compounds identified by GC—MS-analyses (in the diesel fractions) were typical aromatic and cycloparaffin compounds. Normal-and iso-paraffin compounds were not detected. By varying the distillation cut point from 135 to 180°C, the cetane number of the residual diesel fraction improved from 37 to 44. This increase is ascribed to the removal of aromatic compounds in the 135–180°C boiling point range.     

Changes in physicochemical properties of active carbon within a grain

Commercial active carbons were subjected to abrasion in a spouted bed and as a result, active carbons, with external layers removed to different degrees, were obtained. For active carbons so obtained, physicochemical properties were determined from densimetric and adsorption investigation.It was found that radial changes in the properties of active carbons resulted from the nature of the activation reaction.It seems that the method of working by abrasion in spouted beds can also be used for investigating other processes taking place in fluid—solid system.     

Uptake of 226radium and 228radium by the lichen genus Umbilicaria

The 226Ra and 228Ra content of the lichens Umbilicaria cylindrica, U. deusta, U. murina and U. hirsuta has been determined as a function of the growth altitude above sea level, based on data derived from material collected from localities in southwest Poland. These data are interpreted as graphs and formulae to show the influence of environmental factors, particularly altitude, on the concentration of 226Ra and 228Ra, and the coefficients of accumulation calculated.     

Protein-lipid interactions in concentrated infant formula

Radiolabeled milk proteins ([carbon-14] beta-lactoglobulin or [carbon-14] kappa-casein) were added to raw skim milk used to prepare concentrated humanized infant formula. Ultracentrifugation of the sterilized product allowed separation of three fractions: lipids and the proteins associated with them; free casein micelles and other dense particles; and the fluid phase. Distribution of radiolabeled tracer proteins or of protein measured by chemical methods among these three phases varied significantly with differences in processing conditions (time and temperature of sterilization) or amount of certain additives (potassium hydroxide or urea). In the range of 0 to 8 meq/L of potassium hydroxide added to the formula after homogenization but before sterilization, the lipid layer content of carbon-14 from [carbon-14] kappa-casein in the sterilized product decreased by 4.7% for each 1 meq/L of added potassium hydroxide. Lipid layer content of protein decreased by 2 g/L (of a total of 32 g/L) for each 1 meq/L potassium hydroxide. Such differences in the structure of the product, related to interactions of protein with lipid, protein, or calcium phosphate, may correlate with physical properties and stability of milk-based lipid-rich products.     

Dewpoints of flue gases for energy-recovery system design and operation

Low temperature corrosion from flue gases is a common problem in energy recovery systems. We present a simple computation procedure to estimate the dewpoint of combustion gases, which is the limiting design temperature to prevent corrosion. If the composition of fuel oil and the percentage of CO₂ or O₂ in the flue gases are known, the air ratio, percentage of H₂O, p.p.m. of SO₃ in the flue gas, and the dewpoint can be estimated with an error of 1.9%. The results indicate that the dewpoint is high because the combustion conditions are not appropriately adjusted, even if low sulfur fuel oil is used. We conclude that both the fuel quality and the combustion conditions are controlling variables in the design and operation of energy recovery systems.     

Azo disperse dyes with polyfluoroalkyl groups attached to the nitrogen atom of the coupling component

A number of new azo disperse dyes with polyfluoroalkyl groups attached to the nitrogen atom of the coupling component have been prepared. The influence of polyfluoroalkyl groups on the colour and properties of azo dyes has been studied. The replacement of hydrogen atoms of the methyl group of the coupling component by polyfluoroalkyl radicals causes a hypsochromic shift of absorption maximum in a neutral solution and deepening of the dye colour in an acid solution. All tested dyes showed a high lightfastness on acetate and polyamide fibres.     

Metal recovery in a pilot-scale rotating cylindrical wiper-blade electrode system

The performance of an experimental pilot-scale electrochemical reactor using a rotating cylindrical electrode equipped with wiper blades is described. Data obtained from monopolar depositing and bipolar stripping—depositing of copper from dilute aqueous electrolytes are presented and certain economic aspects of metal recovery are discussed.