Temperatures dielectric constants

Impact strength Yield temperature Dielectric constant Power factor (10 Hz)... 

Capacitance measurements are quite simple. A typical drawback is the need of coaxial cables that introduce a thermal load which is not negligible in low-power refrigerators. On the other hand, capacitance bridges null the cable capacitance. Multiplexing is more difficult than for resistance thermometers. In principle, capacitors have low loss due to Joule heating. This is not always true losses can be important, especially at very low temperatures. Dielectric constant thermometers have a high sensitivity capacitance differences of the order of 10-19F can be measured. 

As in the nonelectrolyte case, the problem of representing the thermodynamic properties of electrolyte solutions is best regarded as that of finding a suitable expression for the non-ideal part of the chemical potential, or the excess Gibbs energy, as a function of composition, temperature, dielectric constant and any other relevant variables. 

Data from Ref. 36. b Room temperature dielectric constant. 

A time averaged diffuse layer where ions are attracted to or repelled from the interface by electrostatic forces, but which are also affected by thermal collisions. The effective depth of the diffuse layer is a function of electrolyte concentration, temperature, dielectric constant of the solvent, etc. 

Chem. 60, 1140-2 (1956). Theory of entropy. Curie temperature, dielectric constant of ice. 

F i g u r e 7 is a plot of normalized capacitance of 85, 95 and 100 v/o BT. All these samples show sharp transition. Figure 8 is a plot of Curie temperature as a fiinction of composition. 75 v/o sample shows a Curie point 16°C. Figure 9 is a dielectric response of a multilayer thick film on a Pt substrate made from titanate/ethanol suspensions of composition 100,75, 50 and 25 v/o BT. This sample shows broad transition temperature (80°-120"C). Although pure BT has a transition temperature 120 C and next nearest transition temperature by 75 v/o BT( 16"C). This indicates inter-layer diffiision of the cation resulted the broadening as well as shifting of the peak towards lower temperature. Dielectric constant at transition temperature is -5,000 in IkHz. This preliminary results indicate that by chosing appropiate suspension composition, individual layer thickness and sintering time and... 

The specified values of s are considered as the low-frequency value of n2. Usually, the low-temperature dielectric constant (or refractive index) is slightly lower than that at RT [88]. LHeT values of s for group-IV crystals have also been obtained indirectly from a comparison between experimental and calculated line spacings of shallow donor impurities (see Table 5.3). 

The silver halides, with the exception of one crystal modification of Agl, have cubic crystal structures. Crystal structure data, relevant lattice properties and low temperature dielectric constants, are collected in Table 3. AgF, AgCl, and AgBr all have the NaCl rocksalt structure in which there are four silver halide pairs per nonprimitive unit cell with cation-anion nearest neighbor distances equal to one-half a lattice constant. 

Flexibility at low temperatures Coefficient of friction Stability at high temperatures Dielectric constant Dissipation factor Arc resistance Volume resistivity Surface resistivity Insolubility Chemical resistance Weatherability Surface energy Flame resistance... 

Here a = a (T—T ), being the transition temperature for the corresponding racemate, b>0 and is temperature independent, k the elastic constant, e the high temperature dielectric constant (i.e., in the absence of ferroelectricity), // and C are the constants describing respectively the... 

Coefficient of expansion at 55 C Color, Pt-Co scale Critical pressure Critical temperature Dielectric constant at Z0 C... 

Boiling point Critical temperature Critical pressure Decomposition temperature Dielectric constant at 4 C. Electrical conductivity... 

Physical properties of the first-shell water of macromolecular water shell differ from the bulk water properties. Some of them can be measured experimentally. They are the phase transition temperature, dielectric constant, NMR relaxation parameters, calorimetric characteristics, kinetic characteristics, such as self-diffusion coefficient and some others. The rrrain factors that define protein structure are residue sequence, hydration, iorric arrd hydrophobic irrleractions. 

Figure 46.22 presents [73] the low temperature dielectric constant for a series of emeraldine hydrochloride samples plotted against the square of the crystalline coherence length, (as measured by x-ray diffraction). For low temperatures, is proportional to independent of the direction of orientation of the sample with regard to the microwave frequency electric field. This demonstrates that the charge is delocalized three-dimensionally within the crystalline regions of these samples. Using a simple metallic box model [73,143],... 

TABLE 46.4. Low temperature dielectric constant, smvi T -> 0) and derived metallic box size, L T -> 0), compared to the x-ray diffraction determined coherence length, for typical modestly conducting polymers. 

Specific gravity Tensile modulus Flexural modulus Tensile strength Flexural strength Impact strength Thermal expansion Heat deflection temperature Dielectric constant Volume resistivity Water absorption... 

Here a is the bulk ionic or dc conductivity is the angular frequency (27rf) r is the dipole relaxation time is the relaxed dielectric constant or low frequency/high temperature dielectric constant (relative permittivity due to induced plus static dipoles) is the unrelaxed dielectric constant or high frequency/low temperature dielectric constant (relative permittivity due to induced dipoles only) o is the permitivity of free space E p is the electrode polarization term for permittivity and E"-p is the electrode polarization term for loss factor. The value of E p and E"p is usually unity, except when ionic conduction is very high (75). 

This chapter focuses on the composites of glass and ceramic (especially alumina) that are most commonly used for LTCCs, and it describes the important points for development of materials that meet the requirements for the qualities of LTCCs - firing temperature, dielectric constant, dielectric loss, thermal expansion, strength, and thermal conductivity. This information can also be applied to high dielectric constant LTCCs in which alumina is replaced with perovskite oxides. 

Thermal analysis (TA) consists of a family of analytical techniques in which a property of the sample is monitored against time or temperature while the temperature of the sample is programmed. The properties include weight, dimension, energy take-up, differential temperature, dielectric constant, mechanical modulus, evolved gases, and other, less common attributes. The application of thermal analysis is widespread within the polymer and elastomer industries. Thermal analyzers are used to qualify a material for fitness of use and to troubleshoot processing problems. Thermal analysis consists of three primary techniques that may be used individually or in combination ... 

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