Some Historical Background

With the advent of modem IR detectors, the precision measurement of thermal energy radiating from surfaces that do not glow visibly became possible. Measurements of cool surfaces, well below 0°C, are routinely accomplished with even the least expensive of IR sensors. 

Herschel went on to establish that radiant heat, like light, can refract through materials and reflect off surfaces. It is interesting to note that all of these observations were made at a time when both light and radiant heat were thought to consist of material particles. 

The first cyclone patent was granted to John M. Finch of the United States back in 1885 and assigned to the Knickerbocker Company. Although the dust collector , as it was then called, contained the essence of today s modern cyclones (see Fig. 1.1.1), the dust was allowed to exit out the side of its cylindrical body, rather than out a conical-shaped bottom. It was also a rather complex device and bore little resemblance to today s modern cyclones. 

Improvements in the design of cyclones rapidly followed (at least rapid for the times) and, by the early 1900 s, there began to appear cyclonic devices 

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My improved machine separates the dust from the air by its own momentum in an extremely simple manner, it employs no moving parts, (and) is very simple in construction... 

Due to their simple construction, low manufacturing cost, compactness, lack of moving parts, and relative ease of maintenance, cyclones continued to grow in popularity and improve in both construction and operation. By the 1920s they began to take on the features that characterize today s modern cyclones, as evidenced by two flourmill cyclones shown in Fig. 1.1.3. 

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Time Averages, Ensemble Averages and Some Historical Background... 

The opening chapter gives some historical background to the investigation of high-energy processes. The discussions in the subsequent chapters proceed from current studies in the gas phase, to examination of liquid-phase techniques, and finally to applications in the solid state. The final chapters provide a perspective on current and future industrial applications of the field. 

Hitchman, M. L. and Hill, H. A. O., Electroanalysis and electrochemical sensors . Chemistry in Britain, 22, 1117-1124 (1986), provides a lively, general introduction to this subject, giving details of sensors based on potentiometry, such as ISEs, together with some historical background. 

Fluorine Chemistry Simons, J. H., Ed. Academic New York, 1950-1964 Vol. I-V accounts of all branches of the subject, with some historical background, are in this series. 

Chapter 1 gives an introduction to the book some historical background, the purpose of the book, and some basic information on chemical information systems. 

The first section contains overview and introductory material, some historical background, summaries of the present state of knowledge, and other general topics applicable to all fossil fuel These include environmental consequences of fossil fuel combustion, polysulfide chemistry, microbial metabolism of sulfur compounds, and a review of methods for isolating sulfur compounds from petroleum. 

This chapter begins with some historical background to put NMR into perspective and concludes with a survey of the topics that we shall examine in the remainder of the book. 

The transformation of the crystalline into the glassy state by solid-state reactions is extensively reviewed in its theoretical and experimental aspects. First, we give some historical background and describe the thermodynamics of metastable phase formations, adding as well the kinetic requirements for the amorphization process. Then we discuss the different experimental routes into the amorphous state hydriding, thin diffusion couples, and other driven systems. In the discussion and the summary, we close the gap between the melting phenomena and the amorphization and provide a tentative outlook. 

To understand why we have come to the present state of affairs, it is necessary to provide some historical background and to discuss some of the factors that have influenced EPA policy during the 1970 decade. It is my intention then to review some past and present consequences of the changing regulatory scene. I am a toxicologist, one whose job it is to... 

THIS PORTION of the book identifies the reasons for protecting the public. It provides some historical background leading to an emphasis on safety and... 

Porphyrins and phthalocyanines can be used as core, branches, and terminal groups of dendrimers that have been extensively used as bio-inspired models or mimics of natural systems such as hemoproteins and chlorophyll in photosynthesis, but also in host-guest chemistry, biosensors, photodynamic therapy, and catalysis. Aida et al. demonstrated the amplitude of this field in a review of 2009 [98]. In the following paragraphs, some historical backgrounds will be presented before focusing in a topic specifically concerned on the porphyrin-dendrimer electrochemistry and photoinduced electron transfer processes. 

THIS article is an overview of time and frequency technology. It introduces basic time and frequency concepts and describes the devices that produce time and frequency signals and information. It explains how these devices work and how they are measured. Section I introduces the basic concepts of time and frequency and provides some historical background. Section II discusses time and frequency measurements and the specifications used to state the measurement results. Section III discusses time and frequency standards. These devices are grouped into two categories quartz and atomic oscillators. Section IV discusses time and frequency transfer, or the process of using a clock or frequency standard to measure or set a device at another location. 

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