The 3-space of a universe model is defined at a certain simultaneity. Hence space depends on which time is used. We find a general formula generating all known and also some new transformations to conformally flat spacetime coordinates. A general formula for the recession velocity is deduced.
A fast and specific method for the determination of glyphosate in cereals is described. The method is based on extraction with water by ultrasonication. The samples are cleaned up and separated by high-performance liquid chromatography on a polystyrene-based reverse-phase column (clean-up) in series with an ion chromatography column (separation) using NaHCO(3) as eluent. A micro-membrane suppressor was inserted after the separator column to remove the Na(+) ions before detection by electrospray ionization mass spectrometry in the negative-ion mode. In MS/MS, mode the following transitions were monitored m/z 168--> 150 (glyphosate) and 170-->152 (internal standard 2-(13)C(15)N-glyphosate) for quantification. The mean recovery was 85% (n=32) at spiking levels from 0.03 to 0.33 mg kg(-1). From 1998 to 2001, from the analysis of about 50 samples per annum, a reduction in the glyphosate residues was observed owing to a Danish trade decision not to use grain with glyphosate residues for milling or bread production.
We find a class of solutions of Einstein's field equations representing spacetime outside a spinning cosmic string surrounded by vacuum energy and a rotating gas of non-spinning strings of limited radial extension. Outside the region with vacuum energy and cosmic strings there is empty space. We show that there exist closed timelike geodesics in this spacetime.
We deduce general expressions for the line element of universe models with negative and vanishing spatial curvature described by conformally flat spacetime coordinates. The empty Milne universe model and models with dust, radiation and vacuum energy are exhibited. Discussing the existence of particle horizons we show that there is continual creation of space,matter and energy when conformal time is used in Friedmann-Robertson-Walker models with negative spatial curvature.
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