Al dielectric properties

Hill, N. E. et al. Dielectric properties and molecular behavior. London Van Nostrand Reinhold 1969... 

N. Hill et.al., Dielectric Properties and Molecular Behaviour, Van Nostrant, New York (1969). ... 

The observation of slow, confined water motion in AOT reverse micelles is also supported by measured dielectric relaxation of the water pool. Using terahertz time-domain spectroscopy, the dielectric properties of water in the reverse micelles have been investigated by Mittleman et al. [36]. They found that both the time scale and amplitude of the relaxation was smaller than those of bulk water. They attributed these results to the reduction of long-range collective motion due to the confinement of the water in the nanometer-sized micelles. These results suggested that free water motion in the reverse micelles are not equivalent to bulk solvation dynamics. 

Larsson Brelid, P., Simonson, R. and Risman, P.O. (1999). Acetylation of wood using microwave heating. Part 1. studies of dielectric properties. Holz als Roh- und Werkstoff, 57(4), 259-263. 

A good discussion of the dielectric properties of a mixture, independent of a specific model, has been given by Landau and Lifshitz (1960) we also recommend a paper by Niklasson et al. (1981) for its discussion of several aspects of the mixture problem. 

Equations for calculating van der Waals interaction forces/energies between macromolecules or colloidal particles are quite well established (Israelachvili, 1992 Dickinson and McClements, 1995 McClements, 2005). (For example, see equations (3.35) and (3.36) in chapter 3). The interactions between nanoparticles are potentially more complicated, however, because the nanoparticle size and interparticle separation are comparable in magnitude, precluding the use of the asymptotic forms of the equations also nanoparticles are commonly anisotropic, and their dielectric properties are often not known (Min et al., 2008). 

Several workers have employed monomodal cavities for microwave chemistry on the sub-gram scale. In some cases in which monomodal cavities have been used7, special benefits of so-called focussed microwaves have been claimed. As mentioned earlier, the dielectric properties of a sample can alter substantially with temperature and/or with changing chemical composition. Hence, regardless of whether multi-modal or unimodal cavities are employed, frequent tuning may be necessary if heating efficiency is to be retained. This aspect has often been overlooked by proponents of focussed microwaves. The nett result is that transfer of microwave conditions between monomodal to multi-modal cavities is usually facile. With the MBR (which had a tunable multimodal cavity), Cablewski et al. performed five reactions that had been conducted earlier on the gram scale or below with focussed microwaves (T. Cablewski, B. Heilman, P. Pilotti, J. Thorn, and C.R. Strauss, personal communication see also Ref. 117 for conference poster). These were scaled-up between 40- and 60-fold and reaction conditions... 

The temperature dependence of the dielectric properties of foods has been extensively measured and reviewed by Bengtsson and Risman (1971) and Buffler (1993). Mudgett et al. (1977) has pioneered the prediction of dielectric properties of foods as a function of constituency and temperature. Prediction of the temperature behavior of dielectric properties is crucial for accurate mathematical modeling of foods. Many workers today still use constant room temperature values or a look-up table at best. In the author s opinion, dielectric prediction of food properties is still a very fertile and useful research field. 

Molecular reorientations at Bjerrum fault sites are responsible for the dielectric properties of ice. A second type of fault (proton jumps from one molecule to a neighbor) accounts for the electrical conductivity of ice, but cannot account for the high dielectric constant of ice. Further discussion of such ice faults is provided by Franks (1973), Franks and Reid (1973), Onsager and Runnels (1969), and Geil et al. (2005), who note that interstitial migration is a likely self-diffusion mechanism. 

Characteristic frequencies may be found from dielectric permittivity data or, even better, from conductivity data. The earlier data by Herrick et al. (6) suggest that there is no apparent difference between the relaxation frequency of tissue water and that of the pure liquid (7). However, these data extend only to 8.5 GHz, one-third the relaxation frequency of pure water at 37°C (25 GHz), so small discrepancies might not have been uncovered. We have recently completed measurements on muscle at 37°C and 1°C (where the pure water relaxation frequency is 9 GHz), up to 17 GHz. The dielectric properties of the tissue above 1 GHz show a Debye relaxation at the expected frequency of 9 GHz (8 ) (Figure 3). The static dielectric constant of tissue water as determined at 100 MHz compares with that of free water if allowance is made for the fraction occupied by biological macromolecules and their small amount of bound water (1, 9). 

Frey, M.H. et al. (1998) The role of interfaces on an apparent grain size effect on the dielectric properties for ferroelectric barium titanate ceramics, Ferroelectrics, 206-207, 337-53. 

The radiation effects on dielectric properties of an epoxy resin (Epilox EG 34 with aromatic amine hardener Nr 105) were studied by Jahn et al. with electron,... 

Nunes et al. wanted to find out whether transistors made with PHS and other organic dielectrics could show the excellent performance already reported for the pentacene transistors. This will help to determine whether other polymers with improved characteristics can be found. They investigated the effect of PHS on important device characteristics, threshold voltage and subthreshold slope. The dielectrics they investigated and their dielectric properties are shown in Fig. 6.22. Measured mobilities in transistors fabricated... 

The first attempt to relate changing dielectric properties to kinetic rate equations was by Kagan et al.S9), working with a series of anyhydride-cured epoxies. Building on Warfield s assumed correlation between d log (g)/dt and da/dt, where a is the extent of epoxide conversion, they assumed a proportionality between a and log (q), and modeled the reaction kinetics using the equation... 

Distributed circuit methods use coaxial lines, waveguides and resonant cavities at microwave frequencies. The circuits are designed for measuring an attenuation factor and a phase factor, from which sample dielectric properties can be calculated. The sample may form the dielectric medium between the two conductors of a coaxial line (Scaife et al, 1971), or an open coaxial line is brought into contact with the sample surface (Roussy and Pearce, 1995). Fagan et al, (2004) used an open coaxial line method to demonstrate that the moisture and salt contents of processed cheese could be predicted by measuring dielectric properties over a range of frequencies. 

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