. ABBREVIATIONS xxxv 1 INTRODUCTION 1 1 .1 Background Information, 2 1. 1 .1 What Is HPLC?, 2 1. 1.2 What Can HPLC Do?, 4 1. 2 A Short History of HPLC, 6 1. 3 Some Alternatives to HPLC, 8 1. 3 .1 Gas Chromatography. Special Forms of HPLC, 12 1. 4 Other Sources of HPLC Information, 12 1. 4 .1 Books, 12 1. 4.2 Journals, 13 1. 4.3 Reviews, 13 1. 4.4 Short Courses, 13 1. 4.5 The Internet, 13 References, 15 2 BASIC CONCEPTS. Reciprocating-Piston Pumps, 10 4 3.5 .1. 1 Dual-Piston Pumps, 10 8 3.5 .1. 2 Accumulator-Piston Pumps, 10 8 3.5 .1. 3 Active Check Valve, 10 9 3.5.2 On-line Mixing, 10 9 3.5.2 .1 High-Pressure Mixing, 10 9 3.5.2.2