HIGH-TEMPERATURE EXPERIMENTAL TECHNIQUES

Recently a fairly inexpensive way of high-temperature experimentation has been found to investigate refractory sulfides and related multicomponent systems up to temperatures of nearly 2000 °C using resistance furnaces. These techniques are discussed below and applied to some sulfide systems, in particular of those metals which belong to the VI-B group. The binary systems chromium-sulfur, molybdenum-sulfur, tungsten-sulfur, as well as some other ternary and quaternary systems and their reactions are reviewed and completed within the limits of the new experimental procedure. 

Concentration/separation of sample solutes is one of most important functions in micro- and nanofluidic systems. TGF has proved to be a promising technique that can achieve concentration and separation in microfiuidic devices. However, so far very limited experimental and theoretical investigations have been reported. Experimentally, it is highly desirable to develop various microfiuidic structures that can be utilized by the TGF technique to cmicentrate different samples. Furthermore, more experiments should be carried out to characterize the thermoelectrical properties of buffers and samples so as to obtain the temperature-dependent electroosmotic mobility and electrophoretic mobility, as well as buffer conductivity, viscosity, and dielectric permittivity for each individual sample and buffer solution. In addition, the development of reliable, accurate, high-resolution, experimental techniques for measuring fiow, temperature, and sample solute concentration fields in microfiuidic channels is needed. Theoretically, the model development of TGF is still in its infancy. The models presented in this study assume the dilute solute sample and linear mass flux-driving forces correlations. However, when the concentrations of the sample solute and the buffer solution are comparable, the aforementioned assumptions break down. Moreover, the channel wall zeta potential in this situation may become nonconstant. More comprehensive models should be developed to incorporate the solute-buffer and solute-channel wall... 

Shock-wave data have seen most applications in the measurement of density at high pressure. Other properties of compressed condensed materials whose measurements are discussed in this chapter include sound speed and temperature. Review articles by Grady (1977), Yakushev (1978), Davison and Graham (1979), Murri et al. (1974), Al tshuler (1965), and Miller and Ahrens (1991) summarize experimental techniques for measuring dynamic yielding. 

Over the past decades, advances have been made that reduce environmental impacts of coal burning in large plants. Some arc standard and others experimental. Limestone (mainly calcium carbonate) scrubber smokestacks react with the emitted sulfates from the combustion and contain the chemical products, thereby reducing the release of SO., into the atmosphere by a large factor (of ten or more). Pulverization of coal can also allow for the mechanical separation of some sulfur impurities, notably those in the form of pyrites, prior to combustion. Currently deployed—with more advanced versions in the development stage—are various t yies of fluidized bed reactors, which use coal fuel in a pulverized form, mixed with pulverized limestone or dolomite in a high temperature furnace. This technique reduces sulfate release considerably. There are... 

Shear viscosity is a measure of the ahihty of one layer of molecules to move over an adjacent layer. Bulk viscosity will be mentioned in Section V.2. Since viscosity usually refers to shear viscosity, the term will he used in this way unless otherwise stated. Recommended techniques for measuring the viscosity of high-temperature melt are given below. Experimental data are available from the database mentioned in Section 1.2. Data on viscosities of slags (7 single component systems, 35 two-component... 

In this chapter, we explore how we can use chemical analyses and pH determinations made at room temperature to deduce details about the origins of natural fluids. These same techniques are useful in interpreting laboratory experiments performed at high temperature, since analyses made at room temperature need to be projected to give pH, oxidation state, gas fugacity, saturation indices, and so on under experimental conditions. 

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