First electronic instrument

Subsequently Ishibashi and Fujinaga in Japan pursued a line of development based also on mechanical switching of potential, while in England Barker and coworkers built the first electronic instruments. The advent of solid-state electronics made possible broad commercial development of instruments which in turn extended pulse techniques to other electrodes and stimulated applications. Computer-and microprocessor-controlled instruments have expanded the use of pulse techniques and encouraged development of specialized waveforms. 

These developments were all based on the dropping mercury electrode and in each case the central feature is the instrument which is the embodiment of the technique. The developments of Barker are particularly significant because his was the first electronic instrument and because it was soon commercialized by Mervyn Instruments as the Mervyn-Harwell Square Wave Polarograph. A photograph of this instrument is shown in Figure 2. This pattern was to prove increasingly important because the electronic implementation of pulse voltammetric techniques required expertise and time outside the reach of the average scientist. Thus the use of these techniques would depend on the availability at an acceptable price of reliable commercial instruments. 

Figure 2. The first electronic instrument the Mervyn instruments Square-Wave Polarograph, circa 1958.

The very first spectroscopic instruments, from Newton s prism and pinhole to Frauenhofer s simple spectroscope, were constructed to observe luminescence. Even though the great sensitivity of luminescence detection seemed to promise that luminescence would become an important tool for chemical analysis, the fact is that absorption spectroscopy was the first spectroscopic technique to be widely used. At first glance, this may seem surprising since absorption spectroscopy is inherently less sensitive and had to await the development of more complex instrumentation, especially, electronically amplified detection. 

Microprobe analysis was initially developed at the University of Paris by R. Castaing, who fitted an X-ray spectrometer to a converted electron microscope in the early 1950s, and the first commercial instrument, developed in France by the Cameca company, appeared in 1958. The following years saw commercial instruments produced in the UK, USA and Japan. 

The first electron microscope was built in Germany in 1931 by Knoll and Ruska (Ref 2). Its principles were based on previous works of L. de Broglie (1924), Busch(1926) and others. The first electron microscopes gave images inferior to those obtained by optical microscopes, but by 1934 a quite satisfactory instrument was obtained by B. von Borries, E. Ruska and M. Knoll. Commercial production of electron microscopes was begun in 1939 by Si emens and Halske, AG, Berlin. These instruments (the total number built was about 30) used electromagnetic.lenses... 

All of these instruments were designed to give enlargements of the source emitting electrons. The first electron microscope which could magnify objects not being electron sources was built in 1940 by H. Mahl and H. Bruchs. It was a transmission type electrostatic microscope... 

The basic method is to use a manual Abbe refractometer to determine refractive index. Various automated or electronic instruments exist which automatically perform some of the steps of the manual procedure. The first requirement is that the sample be a solution. In some instruments, the solution is placed between two prisms, and the image of the critical ray boundary is adjusted to meet a reference mark for this adjustment, the refractive index and equivalent °Brix can be read from a scale. The sample temperature must be known, or the instrument must have temperature compensation. Some automatic digital refractometers use the same methodology of sample presentation, but automate the matching of the critical boundary to the reference marker. 

Characterization of materials in the solid state, often loosely referred to as materials characterization, can be a vast and diverse field encompassing many techniques [1-3]. In the last few decades, revolutionary changes in electronic instrumentation have increased the use of highly effective automated instruments for obtaining analytical information on the composition, chemistry, surface, and internal structures of solids at micrometer and nanometer scales. These techniques are based on various underlying principles and cannot be put under one discipline or umbrella. Therefore, it is important first to define the scope of techniques that can be covered in one chapter. 

James and Martin soon developed a gas-density balance as a detector, but the sensitivity of GLC was increased enormously when the argon ionization detector was invented by James Lovelock it was he who also produced the electron capture detector in conjunction with S. R. Lipsky in 1959.162 The flame ionization detector originated in the same year.163 Another important advance in the early days of GLC was the introduction of capillary columns, which were first used by M. J. E. Golay in 1956.164165 The development of some of the first commercial instrumentation has been described.166167... 

At first sight, instrumentation, even physical instrumentation within organic chemistry, may not appear to be an interdisciplinary area. However, if by interdisciplinary we mean an intellectual zone where scientists from different disciplines meet and interact, no field could be more deserving of the title. Not only did the construction of these instruments draw on new developments in electronics and optics and stimulated further innovation, but the techniques themselves came from outside organic chemistry. Nuclear magnetic resonance and mass spectroscopy, to give just two pertinent examples, crossed over from physics, and organic chemists had to collaborate with chemical physicists to obtain the best results from these new techniques. 

As with VCD, the first ROA instruments were built around single-channel scanning dispersive spectrometers [18,19,76,77], Photomultipliers with dualchannel photon-counting electronics were used to record the spectra. Scanning rates were no faster than 1 cm l per minute because of the requirement to accumulate at least 10 7 counts per spectral location, and preferably 10 . Applications with these instruments were limited to samples with favorable Raman scattering and the goals of these early studies were simply to explore the nature of ROA spectra and to improve measurement techniques. Several reviews... 

In 1949 Herzog and Viehbock reported a novel ion source for mass spec-trography (Fig. 4.2) [9]. This source provided separate accelerating fields for the primary and secondary ions and thus became the first modem instrument designed specifically for SIMS. The design included acceleration of the positive secondary ions from an equipotential surface through an electric field acting as an electron-optic lens. 

The orbitrap is an electrostatic ion trap that uses the Fourier transform to obtain mass spectra. This analyser is based on a completely new concept, proposed by Makarov and described in patents in 1996 [26] and 2004 [27], and in Analytical Chemistry in 2000 [28], A third patent describes a complete instrument including an atmospheric pressure source [29], Another article was also published with Cooks in 2005 [30]. The first commercial instrument was introduced on the market by the Thermo Electron Corporation in June 2005. 

Applications Polymers are nonmagnetic materials but they can be modified by fillers. Plastic magnets, first introduced in 1955, are inferior to cast and sintered magnets but have many desirable properties such as low cost, ease of production, better uniformity and reproducibility. Plastic magnets are used in electronic instruments, communication, household utensils, and audio equipment. 

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