The LHC test string: first operational experience

CERN operates the first version of the LHC Test String which consists of one quadrupole and three 10-m twin aperture dipole magnets. An experimental programme aiming at the validation of the LHC systems started in February 1995. During this programme the string has been powered 100 times 35 of which at 12.4 kA or above. The experiments have yielded a number of results some of which, like quench recovery for cryogenics, have modified the design of subsystems of LHC. Others, like controlled helium leaks in the cold bore and quench propagation bewteen magnets, have given a better understanding on the evolution of the phenomena inside a string of superconducting magnets cooled at superfluid helium temperatures. Following the experimental programme, the string will be powered up and powered down in one hour cycles as a fatigue test of the structure thus simulating 20 years of operation of LHC

Essential oils of Satureja boliviana and S. parvifolia growing in the region of Jujuy, Argentina

Essential oils of aerial parts of #Satureja parvifolia and #S. boliviana of Argentina were analysed by GC-MS and GC-FID. Fifty-six components were identified. The main compound of #S. parvifolia essential oil is piperitenone oxide. The most abundant constituents identified in #S. boliviana essential oil were gamma-terpinen, Beta-caryophyllene, germacrene-D, bicyclogermacrene, 1,8-cineol and linalool. (Résumé d'auteur

Essential oils from Zanthoxylum chiloperone and Z. riedelianum growing in Paraguay

Essential oils from aerial parts of #Zanthoxylum chiloperone var. #angustifolium Engl. and #Z. riedelianum$ Engl. have been analyzed by GC/MS. Twenty-four comounds were identified, representing 80% of essential oils. The main components of these essential oils are, respectively, cis-nerolido (71.0%) and spathulenol (65.2%). (Résumé d'auteur

Essential oils from leaves of two Paraguayan Rutaceae : Zanthoxylum hyemale A. St. Hil. and Z. naranjillo Griseb.

Aerial parts of the species #Zanthoxylum hyemale and #Zanthoxylum naranjillo which present the same botanical apparence were subjected to hydrodistillation. Twenty-nine compounds have been identified by GC/MS analysis of the essential oils. Sesquiterpenes such as spathulenol and bicyclogermacrene are the main components. (Résumé d'auteur