The enantioselective synthesis of α-hydroxy esters by ruthenium-catalyzed 1,2-addition of arylboronic acids to tert-butyl glyoxylate is described. The use of RuCl(2)(PPh(3))(3) with (R,R)-Me-BIPAM gave optically active mandelic acids of up to 99% ee. Addition of a fluoride salt such as potassium fluoride (KF) or caesium fluoride (CsF) was effective for achieving high enantioselectivities.

Results are reported of a study of the emission performance of a slit type liquid caesium field ion source which oriqinally was developed by the European Space Research and Technology Centre a s an ion thruster for electric space propulsion. The emission site distribution and the ion beam divergence are examined a s a function of the wetting properties at the emitter slit edge.

A novel [3]rotaxane composed of two 25-membered crownophanes and one axle molecule having two anthryl end groups was successfully synthesized via covalent bond formation followed by aminolysis, and can incorporate caesium ion into the space between the two macrocycles as a 1 : 1 sandwich-type complex, whereas it makes a 1 : 2 complex with lithium ion.

We describe in detail our caesium atom interferometer which uses a combination of microwaves and momentum-changing adiabatic transfer pulses. This combination allows us to achieve spatial separation between the arms of the interferometer. We account for the observed visibility of the resulting interference fringes and find that the effects which contribute the most are optical pumping and magne...

Modelling transport and deposition of caesium and iodine from the Chernobyl accident using the DREAM model J. Brandt, J. H. Christensen, and L. M. Frohn National Environmental Research Institute, Department of Atmospheric Environment, Frederiksborgvej 399, P.O. Box 358, DK-4000 Roskilde, Denmark Received: 11 April 2002 – Accepted: 14 May 2002 – Published: 24 June 2002 Correspondence to: J. Bran...

Abstract The p-type characteristic of solution-processed metal halide perovskite transistors means that they could be used in combination with their n-type counterparts, such as indium–gallium–zinc-oxide transistors, to create complementary metal–oxide–semiconductor-like circuits. However, the performance and stability perovskite-based do not yet match which limit broader application. Here we r...

Following the accident at the nuclear power plant in Chernobyl in 1986, great volumes of Cs were distributed over large parts of the former Soviet Union and Europe. Over Scotland, radiocaesium was deposited as wet deposition. Due to the relatively long physical half-life of 30 years, there are still measurable activity concentrations in the natural environment. This study was made on two organi...