THE DEFINITIVE STANDARDS
Focus
FOR CHLORINATED
DIBENZODIOXINS DIBENZOFURANS PREPARED BY
CAMBRIDGE ISOTOPE LABORATORIES and • Ο Ν
INCLUDING • ISOTOPE LABELED STANDARDS FOR GC/MS DICHLORODIBENZODIOXIN ("C) TETRACHLORODIBENZODIOXIN ("C) ("CI) ("C) PENTACHLORODIBENZODIOXIN ("C) HEXACHLORODIBENZODIOXIN ("C) HEPTACHLORODIBENZODIOXIN ("C) OCTACHLORODIBENZODIOXIN ("C) TETRACHLORODIBENZOFURAN ("C) PENTACHLORODIBENZOFURAN ("C) HEXACHLORODIBENZOFURAN ("C) HEPTACHLORODIBENZOFURAN ("C) OCTACHLORODIBENZOFURAN (1JC)
• UNLABELED CHEMICAL STANDARDS FOR GC AND HPLC TETRACHLORODIBENZODIOXINS PENTACHLORODIBENZODIOXINS HEXACHLORODIBENZODIOXINS HEPTACHLORODIBENZODIOXIN OCTACHLORODIBENZODIOXIN TETRACHLORODIBENZOFURANS PENTACHLORODIBENZOFURANS
vices approach molecu lar dimensions. In addi tion, the interaction of a wide variety of pack aging materials, rang ing from ceramics to metals to polymers, with the device is now of crucial interest. In an introductory lecture Stan Williams from UCLA emphasized that the electrical properties of a surface are influ enced by morphology, chemical composition, and local atomic geom etry and that as many surface techniques as possible must be used to unravel these as pects. Figure 3. 3 5 CI~ ion-induced secondary electron image Charles Evans of of a freshly cleaved surface of SbCI 5 -intercalated Charles Evans and As graphite, 20-/nm full scale sociates and Charles Courtesy of Riccardo Levi-Setti Magee of RCA provid ed state-of-the-art reci pes for the near-surface analysis of electronic materials such as standards, although not at such high Si using SIMS depth profiling and sensitivity levels. Surface analysis Rutherford back scattering (RBS). methods are now also successfully able With SIMS matrix effects mainly un to characterize macromolecular struc der control, it is possible to monitor tures often used in processing of elec one or more secondary ions at the ppb tronic materials. Joe Gardella from level with depth resolution of 10-200 SUNY-Buffalo illustrated how SIMS, Â or to generate secondary ion images HREELS, ESC A, and ion scattering of lateral elemental distributions with spectrometry could be used to study
