Effect of sulphate removal on the surface texture and acid-base properties of TiO2 (anatase)

Commercial anatase containing an appreciable amount of sulphur has been treated for sulphur removal by calcination at increasing temperatures or soaking with aqueous NaOH solutions. It has been found that both methods are active for sulphur removal, but the first one also leads to a sharp sintering of the titania particles. On the other hand, treatment with NaOH_aq leads to incorporation of sodium cations. Both treatments lead also to changes in surface acidity, as measured by Fourier transform infrared (FT-IR) monitoring of pyridine adsorption.     

Recombination lifetime profiling in very thin Si epitaxial layersused for bipolar VLSI

A recently proposed measurement technique (P. Spirito and G. Cocorullo, IEEE Trans. Electron Devices, vol.ED-32, no.9, p.1708-13, 1985) to evaluate the recombination lifetime along epitaxial layers is used to characterize the quality of very thin Si epitaxial layers used for bipolar technology. The experimental results show the ability of the technique to give accurate and detailed information on the quality of epilayers that could be useful in monitoring and improving the growth process. The experimental results show that the lifetime values in thin epilayers are not correlated with doping profiles in the same layers; moreover, they are only slightly dependent on different processes used to make the test devices     

Undesirable sensory properties of the dried pea (Pisum sativum). The rôle of saponins

The rôle of saponins in the undesirable sensory properties of the dried pea P sativum is reported. The sensory properties of isolated soyasaponin I are defined and described as bitter, astringent and metallic. The distribution of saponin in various air-classified pea flour fractions shows that the protein-rich fraction may contain sufficient saponin to cause undesirable tastes.     

A surface distortion analysis applied to the hoop/column deployablemesh reflector antenna

A practical approach is demonstrated for the deterministic analysis of surface distortions in reflector antennas, based on a first-order approximation to the aperture field phase. Measured pattern results from the 15-m-diameter hoop/column deployable mesh reflector antenna are used to demonstrate the accuracy which can be obtained with this surface distortion analysis. The only practical limitation of the first-order approximation is determined by the slope derivations of the distorted surface from the best-fit paraboloid     

Moisture influence on fungal growth in black pepper

The moisture content at which fungal growth proliferated on black pepper was determined at different relative humidities. At 18% moisture content, fungal growth occurred but this was not recorded at the next lower moisture content of 13.9%. Microscopic examination of infected fresh green pepper showed the presence of species of Trichothecium, Colletotrichum and Fusarium. In black pepper, species of Aspergilli and Penicillium were observed.     

The occurrence of goitrogenic substances in milk. 1. Release of goitrin in the milk of cows fed on rapeseed extract cakes

A total of six cows, divided into 3 groups, were fed various amounts of rape cake containing 6 g of goitrin/kg over a period of 7 days. The cows were milked twice a day and the goitrin content of the heated milk samples were determined by a HPLC-method within 2 h. When rape cake was fed at 0.39, 1.9 and 3.9% resp. of the total feed this resulted in medium goitrin values of 37, 163 and 707 micrograms/l milk. These values correspond to a transfer of about 0.1% of the original progoitrin content in the feed. 12 h after the last rape feeding the amount of goitrin in the milk was below the detection limit of 7 ppb. The toxicological significance of these findings are dicussed.