The no-nonsense combination for atomic absorption: Perkin-Elmer's Model 305A with the new HGA-2000 Graphite Furnace.

The new HGA-2000 Graphite Fur­nace, in combination with the Model 305A Atomic Absorption Spectrophotometer, produces ex­cellent detection limits (see Table) with a new degree of convenience, economy, and versatility. With ihe aid of Perkin-Elmer's unique Deu­terium Background Corrector, many solids can be analyzed with­out pretreatment, including plas­tics, biologicals, and papers.

The Furnace itself, which is basi­cally an electrically heated hollow cylinder continuously purged with nitrogen, sits in the large sample space of the 305A. The control unit is placed on the bench beside the instrument. The sample in the Fur­nace can be automatically dried, charred, and atomized at any de­sired temperature (up to 2700°C) for any desired length of time.

More automatic features. In a typical determination, the dry­ing and charring cycles may take from 25 seconds to several minutes. To save operator time and recorder paper, the HGA-2000 can be set so that the recorder starts automatic­ally before atomization, and stops automatically after it.

There is also an automatic means to increase sensitivity. If the oper­ator wishes, the purge gas flow can be cut off at the moment of atomization, and be left off for several seconds. The sample stays longer in the cylinder, and absorb-ance is increased. (Pat. pen.)

DOUBLE BEAM DETECTION LIMITS* HGA-2000

FLAME Graphite Furnace ELEMENT 0*g/ml.) 0*g/ml.) Aluminum 0.02 0.00003 Cadmium 0.0002 0.000001 Chromium 0.003 0.00005 Cobalt 0.01 0.00004 Copper 0.001 0.00001 Gold 0.01 0.00008 Iron 0.005 0.00003 Lead 0.01 0.00006 Nickel 0.002 0.0001 Silicon 0.02 0.00008 Silver 0.002 0.0000025 Zinc <0.001 0.0000006

*S. Slavin, W. Barnett & H. L. Kahn, Atomic Absorption Newsletter 11,37 (1972). (Available free as Rep int AA675.)

The 305A gives performance without frills.

We toll the memorial bell for the famous Model 303, still running re­liably in thousands of laboratories, but now obsoleted by the revolution in electronics. Its replacement: The Model 305A, which uses the same powerful double-beam optical sys­tem and still has moderate cost, but which reads concentration di­rectly, has 200X scale expansion, plugs into a recorder directly, has built-in flame emission, and has a better burner and burner mount.

The result: The 305A has better

Complete HGA-2000/305A System with recorder. Note convenience of controls.

detection limits, speed, versatility, and convenience than the 303, with the same absolute dependability. This combination of virtues was achieved by allowing no compro­mises in performance, but ruthless­ly omitting frills and "sales fea­tures."

A four-dollar word: synergism.

With its normal flame, the Model 305A gives top performance. With many instruments, the HGA-2000 represents a major advance in atomic absorption. However, use them together and you'll believe that they're made for each other. They are.

Send for a free record. On one side is a song entitled, "The Elements", intended to be amusing. On the other side, one can hear "A Diatribe on Detection Limits", which we hope will be useful.

For information and record, write to the Instrument Division, Perkin-Elmer Corporation, 702 Main Ave., Norwalk, Conn. 06856.

PERKIN-ELMER CIRCLE 178 ON READER SERVICE CARD

56 A • ANALYTICAL CHEMISTRY, VOL. 44 , NO. 9, AUGUST 1972