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Rest-frame Strömgren colours are presented for a large number of galaxies in rich clusters between z = 0 and z = 1. Our observations confirm a strong, rest-frame, Butcher-Oemler effect where the fraction of blue galaxies increases from 20% at z < 0.4 to 80% at z = 0.9. After isolating the red objects in each cluster we have compared the mean colour of these old, non-star forming objects with SED models from the literature as a test for passive galaxy evolution in ellipticals. We find good agreement with single burst models which predict an epoch of galaxy formation from z = 2 to 5 (Rakos et al. 1988, 1991; Rakos & Schombert 1993). Although the results demonstrate a great deal of hope for modelling the fine details of colour evolution when our samples are extended into the near- and far-IR, there are reasons to believe that galaxies become, observationally, much more complicated beyond redshifts of 1. The rate of blue colour evolution between 0.6 and 0.9 suggests that by a redshift of 1.5 it will be impossible to tell the difference between galaxies which have completed a single burst at a formation redshift of 2 or ones which are undergoing constant star formation.
GaN based homo- and heterotype LED's have been fabricated and characterized which emit in the blue and ultra-violet part of the spectral range. Complete epitaxial LED layer sequences with different recombination zones have been grown using MOVPE as well as MBE. Subsequent to the material growth, chemically-assisted ion-beam etching and contact metallization are utilized to achieve full LED devices. MBE-grown homotype LED's reveal a peak in the output light spectrum at a wavelength of 372 nm with a linewidth being as narrow as 12 nm. GaN/InGaN LED's grown by MOVPE show visible single peak emission with linewidths of 23 nm. The optical output power as measured in a calibrated Ulbricht sphere is in the 1 μW regime.
Four percent gelatine is an alkaline compound due to NH2 groups, whereas 6% hydroxyethyl starch 130/0.4 (HES130) has acidic features. We investigated whether these solutions lead to differences in acid–base balance in pigs during acidaemia and correction of pH.
Anaesthetized pigs were randomized to HES130 or gelatine infusion (n = 5 per group). Animals received acid infusion (0.4 M solution of lactic acid and HCl diluted in normal saline) and low tidal volume ventilation (6–7 mL kg−1, PaCO2 of 80–85 mmHg, pH 7.19–7.24). Measurements were made before and after induction of acidaemia, before and after correction of pH with haemofiltration (continuous venovenous haemofiltration) and tris-hydroxymethylaminomethane infusion. We measured parameters describing acid–base balance according to Stewart’s approach, ketone body formation, oxygen delivery, haemodynamics, diuresis and urinary pH.
Acid–base balance did not differ significantly between the groups. In HES130-treated pigs, the haemodilution-based drop of haemoglobin (1.4 ± 1.0 g dL−1, median ± SD) was paralleled by an increase in the cardiac output (0.5 ± 0.4 L min−1). Lacking increases in cardiac output, gelatine-treated pigs demonstrated a reduction in oxygen delivery (149.4 ± 106.0 mL min−1). Tris-hydroxymethylaminomethane volumes required for pH titration to desired values were significantly higher in the gelatine group (0.7 ± 0.1 mL kg−1 h−1 vs. HES130: 0.5 ± 0.2 mL kg−1 h−1).
The buffer capacity of gelatine did not lead to favourable differences in acid–base balance in comparison to HES130.
To reduce roll wear and chatter vibrations in its hot strip mill, Eko Stahl carried out roll gap lubrication
trials. The trial equipment, the lubricant and the trials themselves are described. Rolling force and
consequently electric energy consumption were reduced by 8 to 34 % . The automation system
reacted without difficulties to sudden rolling force changes. Three types of torque changes due to roll
gap lubrication have been observed. Chatter vibrations have been suppressed efficiently during
lubrication. Roll wear decreased. Strip thickness and profile tolerances were affected positively, other
quality parameters did not change significantly.
The results of an international project involving five countries and seven laboratories performing over 400 analyses for testing the interlaboratory reproducibility and accuracy using quantitative powder diffraction are presented in this report. Four natural and four artificial mineral mixtures were examined. The RIR (reference intensity ratio) values for all mineral components were either measured or calculated. The relative standard deviation of the interlaboratory determinations range from 5 to 20 percent (for low concentrations, the relative standard deviations can attain 60% percent). Due to systematic errors, the relative standard deviations of the interlaboratory determinations generally exceed the standard deviations determined by individual laboratories. The best results were obtained when the RIR values were measured independendy in each laboratory.
Secondary Neutrals Mass Spectrometry SNMS was used to investigate interdiffusion processes in laser deposited BiSrCaCuO HTSC thin films on various substrate materials. The in-situ deposition of epitaxial Bi2Sr2Ca1Cu2O8+x films requires a substrate temperature just below the decomposition temperature of the 2212 -phase of BiSrCaCuO. This high substrate temperature of about 850°C seems to be the reason for interdiffusion processes of BiSrCaCuO films and MgO(100), YSZ(100) and Si(100) with YSZ or SrTiO3 buffer layers as substrate materials. Therefore, Tc(R=0) of BiSrCaCuO films on silicon with buffer layer is not higher than 70 K at present. SNMS depth profiling gives a more detailed insight into interdiffusion phenomena than other analytical techniques.
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