Major hydrocarbons of the post-pharyngeal glands of mated queens of the red imported fire antSolenopsis invicta

Thin layer and column chromatographic analyses showed that hydrocarbons were the major lipoidal components of post-pharyngeal glands of mated queens of the red imported fire ant,Solenopsis invicta. Gas liquid chromatographic analyses on an OV-17 column showed four major hydrocarbons which have been identified and confirmed by synthesis and comparative mass spectral analyses as 13-methylheptacosane, 13,15-dimethylheptacosane, 3-methylheptacosane, and 3,9-dimethylheptacosane. When microgram quantitites of the natural alkanes on filter paper were placed in colonies of ants, the ants clustered on the paper about the sample and proceeded to masticate the paper in the area containing the alkanes.     

2,4,6-trichloroanisole in broiler house litter: A further cause of musty taint in chickens

Two unknown components in extracts of broiler house litter were identified as 2,4,6-trichloroanisole and 2,4,6-trichlorophenol; the latter compound was also found in extracts of fresh wood shavings. Experiments with pure cultures of fungi isolated from the litter demonstrated that these microorganisms were capable of methylating 2,4,6-trichlorophenol to the chloroanisole. A musty taint in broiler chickens was shown to be due to the presence of 2,4,6-trichloroanisole.     

Chromosome 5 workshop

The clinician engages his penal, private and administrative responsibilities whenever he performs a medical act. Common law applies for private practice, as is the case of most pneumologists. Actually, there is little common law jurisprudence directly concerning pneumological situations. We present here the current trends and recent decisions made by judges faced with cases engaging physician's responsibilities.     

Isolation of high-purity zirconia from Australian zircon sands using an ion-exchange process

Zirconia produced by acid-leaching zircon sand can be significantly contaminated by other elements leached from the sand. A simple cationexchange procedure has been developed that allows separation of the impurity elements from the zirconium to give zirconia with up to 99.99% purity. The addition of formic acid to the acid-leach solution prior to ion exchange provides the removal of about three-quarters of the hafnium present in the product zirconia.     

Ideal versus ought predilections for approach and avoidance distinct self-regulatory systems.

Two studies using different paradigms activated either ideal self-guides (a person's hopes or wishes) or ought self-guides (a person's sense of duty and responsibility) and measured Ss' concern with different forms of self-regulation: approaching matches to desired end states or mismatches to undesired end states and avoiding mismatches to desired end states or matches to undesired end states. A 3rd study asked ideal vs ought discrepant Ss to select among alternative strategies for friendship. The results suggest that a concern with approach is greater for ideal than ought self-regulation, whereas a concern with avoidance is greater for ought than ideal self-regulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Assessment of nitrogen status of soils for cereal crops: Effects of nitrogen fertiliser on growth,composition and yield of spring barley

The effects of fertiliser N on the growth rate and nitrogen and pigment concentrations of spring barley throughout growth were measured at two locations in north-east Scotland in consecutive years. Inorganic N in soil was also measured as were grain and straw yields at maturity. The results show that plant analysis, as early as 3 or 4 weeks after emergence of barley, was an effective assessment of soil N status.     

Size segregation of spherical nickel pellets in the surface flow of a packed bed: Experiments and Discrete Element Method simulations

The size segregation of binary mixtures of spherical nickel pellets flowing into a packed bed was investigated with Discrete Element Method (DEM) simulations and physical experiments in 30 cm and 60 cm wide rectangular test cells. Each test cell approximates a vertical slice of a cylindrical packed bed, with a rising feed tube on one side of the cell representing the stationary frame of reference in the packed bed. As the feed tube is raised, the pellets flow laterally into the test cell to form a sloping surface inclined to the horizontal by the angle of repose. The lateral flow of pellets is confined near the surface of the packed bed, and was intermittent in character (i.e. surging). Velocity vectors show the detailed flow field in the simulated test cells. The smaller pellets were found to be concentrated near the core of the granular assembly, and the larger pellets segregate to the outer wall farthest from the feed tube. The degree of segregation, or coefficient of variation (variance/mean), is proportional to the diameter ratio α of the pellets and the length of the surface, and inversely proportional to the mass fraction of the smaller pellets within the range of parameters studied. The DEM simulations had an average deviation in mass fraction of 0.07 and maximum deviation of 0.22 from the experimental data.     

Size-dependent electrocatalytic reduction of nitrite at nanostructured films of hollow polyaniline spheres and polyaniline–polystyrene core–shells

Nanostructured films of the conducting polymer polyaniline (PANI) were prepared by its potentiostatic polymerization in the presence of thin polystyrene (PS) nanoparticle templates. Two sizes of PS nanoparticles were used (50 and 100 nm) and electron microscopic analysis showed that core–shell composite films of PANI (PANI–PS₅₀ and PANI–PS₁₀₀) and, following removal of the PS, hollow structures (PANI₅₀ and PANI₁₀₀) were formed due to the growth mechanism of PANI around the PS templates. The electrochemical behaviour of the PANI-modified electrodes was studied by cyclic voltammetry, chronocoulometry and amperometry in the presence of nitrite and it was found that nitrite reduction was enhanced by the nanostructuring of the films. The electrocatalysis was dependent on the size of the template, being more pronounced at 50 nm than at 100 nm. The hollow PANI₅₀ film was also a better catalyst than PANI–PS₅₀, whereas for structures based on 100 nm templates, the composite film was better. Such behaviour could be explained in terms of larger surface area and surface concentration of PANI₅₀ and PANI–PS₅₀ films on the electrodes and by higher differential capacitance of those films.     

Methane partial oxidation to synthesis gas over bimetallic cobalt/tungsten carbide catalysts and integration with a Mn substituted hexaaluminate combustion catalyst

Co_0.2W_0.8C_x and supported Co_0.2W_0.8C_x catalysts are shown to be active for the partial oxidation of methane to synthesis gas. The catalyst stability is improved by operating at elevated pressure, or in the presence of excess methane. At atmospheric pressure the Co_0.2W_0.8C_x catalysts deactivate by oxidation, as seen by X-ray diffraction. Manganese substituted hexaaluminate catalysts with different Mn contents have been tested as catalysts for the total combustion of methane. In particular BaMn₂Al₁₀O₁₉ is active and stable for the combustion reaction. The temperature rise observed in the reactor was up to 300 K, depending on the reaction conditions, and complete conversion of oxygen in the feed was achieved. A process for stabilising the carbide catalysts is demonstrated, combining the manganese substituted hexaaluminate total oxidation catalyst, in series before the carbide reforming catalyst: this process leads to stable operation, with no carbon formation in the reactor and no carbide catalyst oxidation observed.