electrochemical detectors for liquid chromatography In 1 9 7 4 BAS introduced the first commercial LCEC system. With over 5 0 0 0 units installed a n d the largest research t e a m t o support them, it's not surprising that our nearest competitors are several generations behind us. Our thin-layer transducers lead the w a y with a w i d e selection of electrode materials in a variety of interchangeable configurations. The latest members of the family are revealed in the n e w LC4B/17 dual electrode amperometry package. Parallel a n d series amperometry can enhance selectivity, detection limits, speed a n d gradient compatibility. Let us show you h o w it's d o n e , no one else can. Write or call for a detailed assessment of your trace analysis problem.
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Here's why IBM HPLC Columns give you superior reproducibility and resolution The secrets in our silica. We combine homogeneous shaped and sized silica with special bonding and packing methods. The result is more uniform βοιυ patterns, unsurpassed stability and excellent reproducibility . . . column-to-column, batch-to-batch.
I B M P a c k i n g : controlled size and uniformly shaped silica spheres pro vide maximum adsorption or partition surface. Flow patterns are uniform for high efficiency and outstanding reproducibility.
Ordinary Spherical Packing: non-uniform size and imperfect shape result in variable surface and flow characteristics. Both resolution and reproducibility suffer.
IBM gives vou p r e m i u m quality H P L C C o l u m n s w i t h o u t a p r e m i u m p r i c e . To o r d e r or ask for further i n f o r m a t i o n , call 8 0 0 - 2 4 3 - 3 1 2 2 . In Connecticut call collect, 2 0 3 - 2 6 5 - 5 7 9 1 . A s k for D e p t . 2 8 . O r w r i t e IBM I n s t r u m e n t s , I n c . , D e p t . 2 8 , P O Box 3 0 2 0 , Wallingford, C T 0 6 4 9 2
Irregular S h a p e d Silica Packing: adsorbent surface and flow patterns can vary- widely. Fractured particles can collect and block flow. Column life is shortened.
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ANALYTICAL CHEMISTRY, VOL. 55, NO. 11, SEPTEMBER 1983 · 1089 A