A new era in Automated Chemistry.
QuickChem™ System IV THE ULTIMATE
IN FLOW INJECTION ANALYSIS.
QuikChem™ delivers up to 1200 results per hour with readouts available within one minute from sample introduction. The system supports complex simultaneous and sequential determinations of multiple ionic analytes in diverse sample matrices. Sophisticated sample pretreatment can be performed including solvent extraction, distillation, dialysis, column treatment and dilution- Complete automation is available for hands-off start-up. sample processing, data reduction/reporting and shutdown And modular design allows you to tailor the system to your specific technical and budget requirements.
Lc
LACHAT CHEMICALS, INC. INSTRUMENT DIVISION 10500 Ν Port Washington Road Mequon. Wisconsin 53092 USA CIRCLE 127 ON READER SERVICE CARD
IT'S NOT EASY... to design and build superior components for liquid chromatography. Otherwise, more people would be doing it! THE REQUIREMENTS of liquid chromatography are very demanding. Products must be able to direct the flow of small volumes of fluids under moderate to high pressure. Internal volumes must be low and very well swept. Materials of construction must be inert to chemical attack by sample or mobile phase. And perhaps most important, products must be designed and manufactured for convenience and reliability. THE SKILL to make products that meet these requirements resides in only a few companies. SSI has been a recognized expert in high pressure technology for fifteen years and was among the first to adopt the internal compression nut for making LC connections. The husky V4-28 thread and 5/16 hex body make the fitting virtually impossible to twist off, and the ferrule and seat have a unique design that allows them to be
sealed easily and reconnected many times without failure. SSI is located a few blocks from The Pennsylvania State University and draws heavily on this technology center for consultants, employees, and continuing education. THE PRODUCTS which result from this combination of requirement and skill include stainless steel fittings (couplings, tees, crosses, column end-fittings) filters, valves, tubing and other special items designed specifically for LC. We are very well known among chemists and engineers who build LC instruments, but not yet among end-users. Please send for our complete catalog and find out more about us.
Scientific Systems Inc.
SSI
1120 W. College Avenue State College, Pa. 16801 USA Phone 814/234-7311
CIRCLE 190 ON READER SERVICE CARD
30 A · ANALYTICAL CHEMISTRY, VOL. 54, NO. 1, JANUARY 1982
mass spectrometer can severely limit mass spectral resolution and produce peak deformation. A second approach is to utilize multiple laser shots until a hole is produced in the sample and a spectrum obtained from the final shot; however, preferential vaporization and migration of some species are likely to produce nonrepresentative analytical results. A third approach is to vapor ize regions of the sample in the ab sence of an electric field on the ion lens. The vaporized material deposits partially on the quartz window (Figure 1) and can then be ionized in the nor mal way. Again, such a procedure is unlikely to provide a representative analysis. Finally, if the sample is transparent to both the pilot and ion ization laser wavelengths, it is some times possible to focus on the reverse side of the sample and produce ioniza tion from that region. This procedure has been used to analyze inclusions in some mineral samples (7). The actual analytical volume in volved in an analysis is a function of both the morphology and composition of the sample. For a very thin (
