Advances in Measurement Technology

Studies of shock-compressed matter have progressed to a point for which detailed, sophisticated technology can probe mechanical responses in considerable detail. The detailed measurements now available appear to provide descriptions beyond that which can be predicted or fully interpreted on an established theoretical basis. As the conditions encountered are so unusual, a heavy reliance must be placed on the credibility of the experiments. Of particular importance is a recognition of the restricted view provided by a particular experiment, from both loading and sample response capabilities. 

Given the advanced state of wave-profile detectors, it seems safe to recognize that the descriptions given by such an apparatus provide a necessary, but overly restricted, picture. As is described in later chapters of this book, shock-compressed matter displays a far more complex face when probed with electrical, magnetic, or optical techniques and when chemical changes are considered. It appears that realistic descriptive pictures require probing matter with a full array of modern probes. The recovery experiment in which samples are preserved for post-shock analysis appears critical for the development of a more detailed defective solid scientific description. 

For mechanical wave measurements, notice should be taken of the advances in technology. It is particularly notable that the major advances in materials description have not resulted so much from improved resolution in measurement of displacement and/or time, but in direct measurements of the derivative functions of acceleration, stress rate, and density rate as called for in the theory of structured wave propagation. Future developments, such as can be anticipated with piezoelectric polymers, in which direct measurements are made of rate-of-change of stress or particle velocity should lead to the observation of recognized mechanical effects in more detail, and perhaps the identification of new mechanical phenomena. 

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In this chapter shock-loading methods measurement of wave profiles physical categories of detectors shock-compression gauges advances in measurement technology. 

Given the rich variety to their broken symmetries, enormous strides in perfecting low molecular weight organic liquid crystal materials for applications in industry, as well as important advances in measurement technologies of material properties under well-controlled conditions, liquid crystals emerge as useful materials to explore the intricate and beautiful interplay in nature between symmetry and spatial dimensionality at phase transitions. 

Despite the first prediction [34] of a measurable PECD effect being a few decades old, it is only in the last few years that experimental investigations have commenced. Practical experiments have needed to await advances in experimental technology, and improvements in suitable sources of circularly polarized radiation in the vacuum ultraviolet (VUV) and soft X-ray (SXR) regions needed for single-photon ionization have been been key here. In the meantime, developments in other areas, principally detectors, also contribute to what can now be accomplished. 

Raman spectroscopy has enjoyed a dramatic improvement during the last few years the interference by fluorescence of impurities is virtually eliminated. Up-to-date near-infrared Raman spectrometers now meet most demands for a modern analytical instrument concerning applicability, analytical information and convenience. In spite of its potential abilities, Raman spectroscopy has until recently not been extensively used for real-life polymer/additive-related problem solving, but does hold promise. Resonance Raman spectroscopy exhibits very high selectivity. Further improvements in spectropho-tometric measurement detection limits are also closely related to advances in laser technology. Apart from Raman spectroscopy, areas in which the laser is proving indispensable include molecular and fluorescence spectroscopy. The major use of lasers in analytical atomic... 

In recent years, rapid advancements in photonic technologies have significantly enhanced the photonic bio/chemical sensor performance, especially in the areas of (1) interaction between the light and analyte, (2) device miniaturization and multiplexing, and (3) fluidic design and integration. This has led to drastic improvements in sensor sensitivity, enhanced detection limit, advanced fluidic handling capability, lower sample consumption, faster detection time, and lower overall detection cost per measurement. 

Abihty to adapt to new advances in the technology of optical measurement, signal processing and data treatment. 

The use of ICG to measure hepatic blood flow and function by spectrophotmet-ric analysis of serial blood samples collected invasively was recognized more than 50 years ago [141], and the concept of non-invasive optical monitoring of physiologic function with ICG is not new [ 142 -146]. However, advances in optical technology and the availability of miniature lasers for biomedical applications have resulted in the development of faster, simpler, and reliable optical methods for monitoring physiologic functions in real-time. While most of these methods rely on the absorption properties of ICG for continuous hepatic func-... 

The selection of the right crystal holder thus plays an important role in all measurements with quartz oscillators. Various crystal holder designs are recommended for the different applications with or without shutter, bakeable for UHV, double crystal holder or crystal six as well as special versions for sputter applications. In addition to these important and more mechanical aspects, the advances in measuring and control technology and equipment features will be discussed in the follovi/ing. 

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