The uncertainty evaluation of CSF2, the second caesium fountain primary frequency standard at PTB, is presented. The fountain uses optical molasses to cool atoms down to 0.6μK. The atoms are launched vertically in a moving optical molasses, and state-selected in the |F = 3,mF = 0〉 hyperfine ground state. During their ballistic flight, the atoms interact twice with a microwave field, thus comple...

The NrtA and NrtB nitrate transporters are paralogous members of the major facilitator superfamily in Aspergillus nidulans. The availability of loss-of-function mutations allowed individual investigation of the specificity and inhibitor sensitivity of both NrtA and NrtB. In this study, growth response tests were carried out at a growth-limiting concentration of nitrate (1 mM) as the sole nitrog...

Tetrazolone (5-oxotetrazole) was synthesized by a moderate strategy through three steps (addition, cyclization and catalytic hydrogenation) avoiding the unstable intermediate diazonium, as reported during the previous preparation. Alkali and alkaline earth metal salts with lithium (1), sodium (2), potassium (3), rubidium (4) caesium (5), magnesium (6), calcium (7), strontium (8) and barium (9) ...

The title compounds were prepared by sintering stoichiometric mixtures of the binary deuterides in an autoclave under 65 bar pressure at 625 K. Neutron powder diffraction reveals a b-K SO type structure for Cs MgD (space group Pnma, a58.5988(4), b56.6234(3), 2 4 2 4 ˚ ˚ c511.5988(5) A) and a Cs CoCl type structure for Cs MgD (space group I4/mcm, a58.4022(2), c512.6951(4) A). In both deuterides ...

The unique electronic and structural characteristics of 1,4-benzoquinones with possibilities for numerous interactions such as coordination, hydrogen bonding accompanied by proton and/or electron transfer, π-interactions, and redox activity, are used by nature to perform important biological reactions. In spite of their wide use in supramolecular chemistry for construction of functional materia...

Earlier studies have indicated that caesium-131 is a good myocardial scanning agent for the demonstration of anterior infarcts. One hundred and ten patients with documented anterior myocardial infarction were studied by 131Cs myocardial scintigraphy. An anterior area of decreased uptake of caesium was noted in all but 3 subjects whose necrotic zone was likely to be of small dimensions. In 20 ca...

Relative measurements of the photoionization by line absorption in caesium vapor with and without foreign gases were made by the space-charge method. If the effect of a collision with a gas molecule is to change the probability of ionization from E to Ef, then the probability E v at a gas pressure p is given by E -Ev E -EfV^ Aa*T'pJ where A is a known constant, a is the distance between atom ce...