Ion t r a p M S The 3DQ Discovery is a quadrupole ion trap mass spectrometer incor porating a radio frequency wave form generator with user-selectable frequency range parameters. The waveform generator provides clean chemical ionization by reducing space charge interferences in the trap. The system can perform CI and EI switch ing within a run and accommo dates a variety of inlet systems. The Field-Noise Filter broad band waveform generator is con trolled through a Windows-based user interface to eject ions of speci fied m/z and prevent the trap ca pacity from being overloaded. The user can program it to select ions with one or several m/z ratios or to select ions in one or more m/z ranges. Ions to be retained in the trap can be selected by specifying "notches" in the band of frequen cies narrow enough to correspond to 1 Da. The spectrometer can per form EI, selected reagent ion CI, SIM, multiple ion monitoring, MS/ MS, MS", and alternating CI and EI within a run. The three posts that hold the ion trap together are heated; their con tact with the end caps and ring electrode heats the trap directly and prevents samples from condens ing on cold surfaces within the trap. The system provides unit mass resolution between 10 and 650 Da, and the mass scan rate can be speci fied in the range of 1000-25,000 Da/s. Hitachi/Teledyne • 412
Separations Catalog lists IC, HPLC, CE, and SFC in strumentation and accessories as well as LC sample preparation stations, detectors, Catalog No. 6 lists sample injectors for analytical-, micro-, or preparative-scale LC and chromatography modules. Liquid chromatographic accessories include separations; high-pressure switching pumps, postcolumn derivation cells, fit valves; low-pressure Teflon valves; and fit tings, valves, and eluent delivery modules. tings, loops, filters, and valve accesso ries. Illustrations and descriptions are ac SFC products include detectors, restrictors, SFC/GC columns, and an SFE sys companied by specification tables. tem. Dionex • 415 Rheodyne 1 4 1 3 CATALOGS
HPLC Catalog lists instrumentation and accesso ries for HPLC, including complete chro matography systems, pumps and solvent delivery modules, injectors, column heat ers and selectors, detectors, and fittings. Rainin 1 4 1 4
Walk-up NMR The Gemini 2000 NMR spectrometer, intended for routine analyses and methods development in industrial and academic laboratories, is controlled by a Sun Microsystems SPARCstation that offers both simplified and ad vanced user interfaces. The system au tomates experiments such as COSY, DEPT, and HETCOR, and can produce simple *H NMR spectra in < 4 min. The simplified user interface pro vides drop-down menus and online help for parameter adjustment and in strument control. For methods devel opment or for more advanced tech niques such as indirect detection, sol vent suppression, the use of pulsedfield gradients, and spin locking, the regular VNMR interface provides data analysis methods such as linear pre diction, digital signal processing, deconvolution, and interactive free in duction decay weighting. The digital sig nal processing software produces single or multidimensional spectra. Probes for specific applications are available with the spectrometer. These include a pulsed-field gradient acces sory for Ή- 1 3 0 NMR and other
For more information, please circle t h e appropriate numbers on one of our Reader Service Cards.
heteronuclear correlation experiments, a probe that allows the user to obtain spectra from microgram and nano gram amounts of sample, and a probe that can be used for NMR of four dif ferent nuclei without the need for tun ing. Oxford superconducting magnets for the spectrometer are available in the frequency range of 200-4000 MHz. Other components included in broad band configurations are high-power lin ear pulse amplifiers, computer-con trolled pin-diode attenuators, and pro grammable filters. Varian 1 4 1 6
Analytical Chemistry, Vol. 66, No. 23, December 1, 1994 1187 A
