MODEL 350-AN ADVANCED COMBINATION OF FEATURES FOR UV-VIS-NIR ANALYSIS Perkin-Elmer's Model 350 Spectrophotom­eter is the product of α completely fresh approach to instrument design. Keyed to

Chaff shows spectral analysis by Optical Rotatory Dispersion of 2mg of fesfosferone in p-dioxane. With identical calcite polarizer-analyzer combinations in each beam, absorption by the sample is canceled out. Rotation of the light by the sample appears as a pen deflection on the chart, whence it is readily con­vertible to angular units by conversion tables provided with the accessory. The high scale expansions available on the Model 350 can be used to advantage in ORD work.

today's demand for sophisticated analy­tical and research capability, it combines all the most-wanted features—each at its maximum potential.

In the range from 175 τημ in the far ultra­violet to 2.7 μ in the near infrared, the ver­satile Model 350 offers superior resolution and photometric precision for a wide range of differential analyses, for color measure­ment, kinetic studies, optical rotatory dis­persion determinations, and other exacting applications. Optically designed for high energy per spectral slit width, with scale

expansion and pen response control, it possesses extraordinary microanalytical sensitivity for sample-limited studies—bio­medical, forensic and other.

A wide dynamic range of scan speeds and complete selection of recording and sam­pling accessories enable the Model 350 to meet specialized analytical requirements with ease. For an illustrated brochure with complete description and specifications, write to Instrument Division, Perkin-Elmer Corporation, 751 Main Avenue, Norwalk, Connecticut.

PERKIN-ELMER

This spectrum of indene and indene— camphor— cyclohexanone was recorded in 16 minutes through use of Model 421 s long-wavelength grating interchange.

NEW MODEL 421 INTERCHANGE GIVES TOP RESOLUTION AT LONGER WAVELENGTHS

Perkin-Elmer's Model 421 Grating Spectro­photometer is already known for its out­standing performance over the basic

infrared spectrum. Now, a new interchange extends this performance into longer wave­lengths. You can have both the basic 4000-550 wavenumber range and the new 2000-250 wavenumber range by a simple switch of interchange assemblies that takes less than five minutes, requires no warm-up time or optical adjustment.

Both interchanges give you true grating resolution — plus the Model 421's top-efficiency f/4.5 optical system that scans

faster and handles samples smaller than any comparable instrument. An integral automatic speed suppression system guar­antees accurate spectra in minimum time, adding to your working efficiency.

Get the whole story on what the Model 421—and its accessories —can do in your own applications. Write today for the new Model 421 brochure. The address: Instru­ment Division, Perkin-Elmer Corporation, 75] Main Avenue, Norwalk, Connecticut.

PERKIN-ELMER

Perkin-Elmer

FIRST HIGH-PRECISION CHROMATOGRAPH SEES, MEASURES ALL COMPONENTS The new Perkin-Elmer Model 226 Gas

Chromatograph is the world's first high-

precision chromatographic instrumental

system.

It employs the most advanced electronic,

pneumatic and thermal control components

and subsystems to optimize the perform­ance of high resolution Golay and packed columns, the flame ionization detector, and the first automatic, truly linear, temperature programming system. Its unmatched speed, resolution, reproducibility, and quantita­tive precision facilitate automatic analysis of virtually any organic mixture amenable to gas chromatographic separation.

For the petroleum chemist who wishes to

resolve all of the components in a gasoline

or gas-oil.

For the biochemist who wishes to analyze

steroids, lipids, amino acids or saccharides

precisely and rapidly.

For the food chemist who must sense and measure the marginal traces of components which contribute to flavor or aroma.

For all chemists who require the finest per­

formance, precision and convenience in

gas chromatographic analysis.

Golay chromatogram above shows sep­aration of 103 components of reformed gasoline in 55 minutes. Note: iso and nor­mal butanes completely resolved at start, naphthalenes at end of run.

For complete information, write Instrument

Division, Perkin-Elmer Corporation, 751

Main Avenue, Norwalk, Connecticut.