International Journal of Mass Spectrometry = ELSEVIER International Journal of Mass Spectrometry www.elsevier.com/locate/ijms Volume 275 Issues 1-3 1 August 2008 Contents ClusterSculptor: Software for expert-steered classification of single particle mass spectra es ae ee, ae nn sy Oe UO os bn no xo Wie eee eae 54566 SNENCN SO One dee RS GSS Sa bedn ah euaawaGdes nnd edaus 1 Numerical observation of preferred directionality in ion ejection from stretched rectilinear ion traps A. Krisnnavem, N. Kumar Verma, AG. MONON ANG AK. MOTMATICY UINGIA) 66... i cc ccc cccncneseccbecedecuccessscccncsccenes 11 Theory of the elliptical Penning trap ee rs Eh elias Ld ga a As wk wd he Nae RENEE TO Ow eed ORNS SNE ORAS ONES WERNER RKO Kode ehekeirceRein 21 The elliptical Penning trap: Experimental investigations and simulations M. Breitenfeldt, S. Baruah, K. Blaum, A. Herlert, M. Kretzschmar, F. Martinez, G. Marx, L. Schweikhard and N. Walsh Craven che keetweraed ed hei wee RRENEREK SLA bw Ss SAGAR EEN dae FN NE SN EREE Cou ROAR e ae Rak eke ao aN eed Ase xehaans 34 Atmospheric pressure photoionization mass spectrometry as a tool for the investigation of the hydrolysis reaction mechanisms of phosphite antioxidants M. Papanastasiou, A.W. McMahon, N.S. Allen, B.W. Johnson, K. Keck-Antoine, L. Santos and M.G. Neumann (Belgium, Brazil, UK) ...... 45 VUV photoionisation of free azabenzenes: Pyridine, pyrazine, pyrimidine, pyridazine and s-triazine G. Vall-llosera, M. Coreno, P. Erman, M.A. Huels, K. Jakubowska, A. Kivimdki, E. Rachlew and M. Stankiewicz (Canada, Italy, Poland, Sweden) ........ 55 An extraction system for low-energy hydrogen ions formed by electron impact a do VAAN Ne SW na UR GR ORA MEST A EAS Odo ke eS UNEKD NSD S TREE OR eR Rb ed ne ea Weneeay OOe 64 230Th isotope measurements of femtogram quantities for U-series dating using multi ion counting (MIC) MC-ICPMS eh SE tata Sch ea ea SAE ies Sete es ane WEEE S Ee eNKA ad ede ERK PRES SEER REEA TA Gd RARE Lek ee Ae 75 Recombination of KrD* and XeD* ions with electrons REvene rman P re ra eae re rere hee ney nner re 80 Emission of molecular fragments synthesized in hypervelocity nanoparticle impacts C. Guillermier, S. Della-Negra, E.A. Schweikert, A. Dunlop and G. Rizza (France, USA) .....ce.ce .ccc. cec.e .cece. cee.eeeceeeeceee es 86 Dipole excitation of ions in linear radio frequency quadrupole ion traps with added multipole fields gs or ny 5 ag PONG DONE SASY HO WON EIT ONCERRHERS TD DAE CUE PERE ER EENORASESER ERP ERET ARES One eei oun 91 (Contents continued on page IV) Abstracted/Contents in: Chem. Abstr.; Curr. Contents, Phys. Chem. Earth Sci.; Embase/Excerpta Medica; INSPEC; Mass Spectrom. Bull.; PASCAL/CNRS. Also covered in the abstract and citation database SCOPUS®. Full text available on ScienceDirect® 1387-3806 (20080801) 275:1/3; 1-T IV (Contents continued from outside back cover) . Tandem mass spectrometric study of ciprofloxacin—poly(ethylene glycol) conjugate in the presence of alkali metal ions >. Hany aes SOCEM, Pa. GAGs, Ci. Pores, bs Seewene Ge PN, ZUG CSUR) oi ek ce pee eee dbeee esse cdaeas 104 Unimolecular chemistry of metastable dimethyl isophthalate radical cations R. Flammang, N. Dechamps, P. Gerbaux, P.-C. Nam and M.T. Nguyen (Belgium, Viet Nam) ....................000- 110 Short communication Monitoring benzene formation from benzoate in model systems by proton transfer reaction-mass spectrometry E. tee, ©. Beesiol, 5. <araee, 5.07, eee, eee Fs eee CME, HOMLY) 2. eee ce thee oe tsa ew yep bun 117 Vol. 275 Iss. 1-3 AUG 1