"Among the many materials investigated in the infrared (IR) field, narrow-gap semiconductors are the most important in IR photon detector family. Although the first widely used narrow-gap materials were lead salts (during the 1950s, IR detectors were built using single-element-cooled PbS and PbSe photoconductive detectors, primary for anti-missile seekers), this semiconductor family was not well distinguished. This situation seems to have resulted from two reasons: the preparation process of lead salt photoconductive polycrystalline detectors was not well understood and could only be reproduced with well-tried recipes; and the theory of narrow-gap semiconductor bandgap structure was not well known for correct interpretation of the measured transport and photoelectrical properties of these materials"--

The polygraph, most commonly known as the lie detector, was created and refined by academics in university settings with support from a few early police agencies. This work is a history of the machine, from the experimental work of the late 1800s that led directly to its creation, until the present. It covers early lie detectors and their inventors from the 1860s to the early 1920s, their use by the police and other law enforcement agencies in the 1930s and their use in Cold War America in the 1940s and 1950s. It then discusses the government's use of the polygraph in the 1960s, the PSE, a new take on the old polygraph, and private businesses' reliance on the polygraph in the 1970s and the government's increasing reluctance to use it in the 1980s. A chapter on new ideas and uses for the polygraph in the 1990s and after concludes the book.

The renaissance of liquid chromatography took place in the late 1960's and early 1970's. The first edition of this book published in 1977 described the detectors that were available at that time and which provided a performance matching that of the contemporary equipment with which they were associated. It is interesting to note that the most popular detectors then (the UV detector, the refractometer detector, the fluorescence detector and the electrical conductivity detector) are still the most commonly used detectors nearly a decade later. Detector design, however, has changed very significantly over the intervening years. Modern high efficiency columns provide very narrow peaks and very fast separations, and thus the physical design of the detectors had to change to meet these new challenges. In 1977, there was little real understanding of the important role played by the detector in the overall function of the chromatographic system and although some of the factors were pointed out in the first edition of this book, in retrospect they appeared to be little understood.This second edition gives an entirely new presentation of the subject of liquid chromatography detectors. It contains sections dealing with the fundamental aspects of the interaction between columns and detectors and the interaction between ancillary equipment and the detector. It brings the reader up-to-date with new designs and novel detecting systems that have been developed since 1977 and extends significantly the subject of the association of the liquid chromatography detector with spectroscopic techniques. In particular the book now explores the association of liquid chromatography with nuclear magnetic resonance, infrared and atomic absorption spectrometry. This book not only gives a comprehensive treatment of the subject of liquid chromatographic detectors and provides a rational procedure for defining their performance and so permit valid comparisons, but also discusses detector performance in relation to the whole of the chromatographic system.

Completely revised and reorganized while retaining the approachable style of the first edition, Infrared Detectors, Second Edition addresses the latest developments in the science and technology of infrared (IR) detection. Antoni Rogalski, an internationally recognized pioneer in the field, covers the comprehensive range of subjects necessary to un

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