A low stray light, high current, low energy electron source

A design of an electron gun system is presented whose stray light emission is reduced by about three orders of magnitude compared to a regular low-energy electron diffraction gun. This is achieved by a combination of a BaO cathode run at rather low temperature and a 30° tandem parallel-plate analyzer used as an optical baffle. The system provides a high beam current of several microampers at 50 eV beam energy. The system can be used down to ∼10 eV

An Infant Formula with Partially Hydrolyzed Whey Protein Supports Adequate Growth and Is Safe and Well-Tolerated in Healthy, Term Infants: A Randomized, Double-Blind, Equivalence Trial

The current study evaluates the safety and tolerance of a partially hydrolyzed whey protein-based infant formula (PHF) versus an in intact cow's milk protein formula (IPF). Breastfed infants were included as a reference group. In a multi-country, multicenter, randomized, double-blinded, controlled clinical trial, infants whose mothers intended to fully formula feed were randomized to PHF (n= 134) or IPF (n= 134) from <= 14 days to 17 weeks of age. The equivalence analysis of weight gain per day within margins of +/-3 g/d (primary outcome), the recorded adverse events, growth and gastro-intestinal tolerance parameters were considered for the safety evaluation. Equivalence of weight gain per day from enrolment until 17 weeks of age was demonstrated in the PHF group compared to the IPF group (difference in means -1.2 g/d; 90% CI (-2.42; 0.02)), with estimated means (SE) of 30.2 (0.5) g/d and 31.4 (0.5) g/d, respectively. No significant differences in growth outcomes, the number, severity or type of (serious) adverse events and tolerance outcomes, were observed between the two formula groups. A partially hydrolyzed whey protein-based infant formula supports adequate infant growth, with a daily weight gain equivalent to a standard intact protein-based formula; it is also safe for use and well-tolerated in healthy term infants

Determination of neo- and d-chiro-Inositol Hexakisphosphate in Soils by Solution 31P NMR Spectroscopy

The inositol phosphates are an abundant but poorly understood group of organic phosphorus compounds found widely in the environment. Four stereoisomers of inositol hexakisphosphate (IP6) occur, although for three of these (scyllo, flea, and D-chiro) the origins, dynamics, and biological function remain unknown, due in large part to analytical limitations in their measurement in environmental samples. We synthesized authentic neo- and n-chiro-IP6 and used them to identify signals from these compounds in three soils from the Falkland Islands. Both compounds resisted hypobromite oxidation and gave quantifiable P-31 NMR signals at delta = 6.67 ppm (equatorial phosphate groups of the 4-equatorial/2-axial conformer of neo-IP6) and delta = 6.48 ppm (equatorial phosphate groups of the 2-equatorial/4-axial conformer of D-chiro-IP6) in soil extracts. Inositol hexakisphosphate accounted for 46-54% of the soil organic phosphorus, of which the four stereoisomers constituted, on average, 55.9% (myo), 32.8% (scyllo), 6.1% (neo), and 5.2% (n-chiro). Reappraisal of the literature based on the new signal assignments revealed that neo- and D-chiro-IP6 occur widely in both terrestrial and aquatic ecosystems. These results confirm that the inositol phosphates can constitute a considerable fraction of the organic phosphorus in soils and reveal the prevalence of neo- and D-chiro-IP6 in the environment. The hypobromite oxidation and solution P-31 NMR spectroscopy procedure allows the simultaneous quantification of all four IP6 stereoisomers in environmental samples and provides a platform for research into the origins and ecological significance of these enigmatic compounds

Simple synthesis of 32P-labelled inositol hexakisphosphates for study of phosphate transformations

In many soils inositol hexakisphosphate in its various forms is as abundant as inorganic phosphate. The organismal and geochemical processes that exchange phosphate between inositol hexakisphosphate and other pools of soil phosphate are poorly defined, as are the organisms and enzymes involved. We rationalized that simple enzymic synthesis of inositol hexakisphosphate labeled with 32P would greatly enable study of transformation of soil inositol phosphates when combined with robust HPLC separations of different inositol phosphates

Erarbeitung der Grundlagen fuer die europaeische Normung von Brennstoffzellen-Heizanlagen fuer die haeusliche Energieversorgung (ENBA). Teilprojekt: Strom- und Waermelastgaenge in Einfamilienhaeusern und Installation von Brennstoffzellenheizungen durch das Handwerk Abschlussbericht TAA-Projekt 5048

As part of a joint ZIP project entitled 'Erarbeitung der Grundlagen fuer die europaeische Normung von Brennstoffzellen-Heizanlagen fuer die haeusliche Energieversorgung (ENBA)' ('Development of the Fundamentals for European Standardisation of Fuel Cell Heating Systems for Residential Energy Supply'), Ruhrgas conducted high-resolution measurements of electricity and heat load profiles in 5 single-family homes during the period from May 2002 to July 2003. In addition, a simulation program for electricity and heat supply to buildings with small CHP systems was prepared and the level of qualifications of craft enterprises required for installing fuel cell heating systems was determined. The buildings selected for the project were three single-family homes and one two-family home (with separate meters), all of which are located in the Ruhr area. These buildings were fitted with the necessary measurement and data transmission equipment. The houses selected were of different construction types to make the data for the 'single-family home' category as representative as possible, despite the low number of measuring points. All data recorded during the above period have been stored in an Access database (approx. 130 MB) and may be retrieved for different purposes. In order to assess the fuel cell system's operating behaviour, a simulation program was developed which determines the load status of the fuel cell system on the basis of measured values for heat and hot water demand and uses this load status to calculate power generation by the fuel cell for comparison with the home's power demand. This makes it possible to determine how much of the power generated by the fuel cell is available for consumption in the house and how much is fed into the grid. The calculations show that the average determined at 15-minute intervals (which is sufficient for the power grid) is far too inaccurate for CHP evaluation purposes. At these intervals the power demand peaks are not properly recorded and simulation results in a deviation up to 10% of the power fed into the grid compared with the 1-minute resolution. The project also confirmed the need for high-resolution load profiles for the purpose of accurately determining fuel cell system economics. An investigation into the qualification of craft enterprises showed that some 2,400 enterprises are qualified to sell and install fuel cell heating systems. All that is still required is product-specific training. (orig.)SIGLEAvailable from TIB Hannover: F04B883 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Wirtschaft und Arbeit, Bonn (Germany)DEGerman

Size-dependent luminescence of small palladium particles

We report cathodoluminescence spectra of small Pd clusters of various size deposited on a thin, well-ordered oxide film. The size distribution of the deposited metal aggregates can be chosen and deliberately varied. The luminescence spectra vary characteristically as a function of the variation of particle size. The resonance energy at the highest luminescence energy with decreasing average particle size vary as expected for electronic states in a quantum confined metal particle. For an average aggregate size of 10 Å the luminescence is maximum

Cathodoluminescence of small silver particles on Al₂O₃/NiAl (110)

Cathodoluminescence experiments have been performed on silver clusters, which were grown on well characterized Al2O3 films supported on (110) NiAl crystals. Cluster size and shape were varied via Ag deposition at different temperatures and annealing the samples afterwards. At an electron energy of 50 eV photon emission was observed at the (1,0) plasmon resonance, which was centered at 3.7 eV for a mean size particle at 10 run. The blue shift of similar to200 meV is interpreted by the oblate shape of the particle, as also indicated by the position of the (weak) emission for the (1,I) plasmon. The underlying NiAl exerts minor influence on the plasmon resonance, as the induced image dipole does not couple to the plasmon because of its phase shift of roughly 90degrees

Structural Investigation of Palladium Clusters on γ-AlO₃(111)/NiAl(110) with Transmission Electron Microscopy

For Pd clusters on γ-Al2O3 epitaxially grown on NiAl(110) the lattice constant has been determined as a function of the cluster size by evaluating patterns induced by double diffraction involving the NiAl substrate and the cluster lattice. Similar to results reported previously for platinum and tantalum clusters on the same substrate (Surf. Sci.1997, 391, 27; Surf. Sci.1998, 413, 192), we observe a reduction of the distances within the lattice with decreasing cluster size. The highest observed reduction is 5% for clusters with a diameter of about 12 Å. Within the limits of the experimental errors the reduction of the lattice distances is isotropic. Although the samples have been exposed to air prior to investigation, the clusters are only weakly oxidized as concluded from XPS data