Solids thermal properties

Y.S. Touloukian, R.W. Powell, C.Y. Ho, P.G. Kle-mens Thermal Conductivity, Non-Metallic Solids, Thermal Properties of Matter, Vol. 2 (IFI/Plenum, New York 1970)... 

For turbulent flow of a fluid past a solid, it has long been known that, in the immediate neighborhood of the surface, there exists a relatively quiet zone of fluid, commonly called the Him. As one approaches the wall from the body of the flowing fluid, the flow tends to become less turbulent and develops into laminar flow immediately adjacent to the wall. The film consists of that portion of the flow which is essentially in laminar motion (the laminar sublayer) and through which heat is transferred by molecular conduction. The resistance of the laminar layer to heat flow will vaiy according to its thickness and can range from 95 percent of the total resistance for some fluids to about I percent for other fluids (liquid metals). The turbulent core and the buffer layer between the laminar sublayer and turbulent core each offer a resistance to beat transfer which is a function of the turbulence and the thermal properties of the flowing fluid. The relative temperature difference across each of the layers is dependent upon their resistance to heat flow. 

The pressure is to be identified as the component of stress in the direction of wave propagation if the stress tensor is anisotropic (nonhydrostatic). Through application of Eqs. (2.1) for various experiments, high pressure stress-volume states are directly determined, and, with assumptions on thermal properties and temperature, equations of state can be determined from data analysis. As shown in Fig. 2.3, determination of individual stress-volume states for shock-compressed solids results in a set of single end state points characterized by a line connecting the shock state to the unshocked state. Thus, the observed stress-volume points, the Hugoniot, determined do not represent a stress-volume path for a continuous loading. 

The theory of Debye is certainly the most complete and successful attempt to represent the thermal properties of solids which has yet been made by the aid of the theory of ergon ic distribution. 

PET, PTT, and PBT have similar molecular structure and general properties and find similar applications as engineering thermoplastic polymers in fibers, films, and solid-state molding resins. PEN is significantly superior in terms of thermal and mechanical resistance and barrier properties. The thermal properties of aromatic-aliphatic polyesters are summarized in Table 2.6 and are discussed above (Section 2.2.1.1). 

Physical, thermal, and chemical stability in order to reduce operating costs, solid sorbents must demonstrate stability under flue gas conditions, adsorption operation conditions, and during the multi-cycle adsorption-regeneration process. In particular, stability in the presence of water vapor is essential for the sustainable performance of the solid sorbent. In addition to thermal properties of the solid sorbent, heat capacity and thermal conductivity are also important in heat transfer operations. 

Thermal Properties and Mechanism of Thermal Decomposition in the Solid Phase... 

US patent 6,723,728, Polymorphic and other crystalline forms cis-FTC [106], The present invention relates to polymorphic and other crystalline forms of (—)-and ( )-cA-(4-amino-5-fluoro-l-(2-(hydroxymethyl)-l,3-oxathiolan-5-yl)-2(lH)-pyrimidinone, or FTC) [106]. Solid phases of (—)-cz>FTC that were designated as amorphous (—)-FTC, and Forms II and III were found to be distinguishable from Form I by X-ray powder diffraction, thermal analysis properties, and their methods of manufacture. A hydrated crystalline form of ( )-cA-FTC and a dehydrated form of the hydrate, were also disclosed, and can similarly be distinguished from other forms of FTC by X-ray powder diffraction, thermal properties, and their methods of manufacture. These FTC forms can be used in the manufacture of other forms of FTC, or as active ingredients in pharmaceutical compositions. Particularly preferred uses of these forms are in the treatment of HIV or hepatitis B. 

In contrast to the strong effect of gas properties, it has been found that the thermal properties of the solid particles have relatively small effect on the heat transfer coefficient in bubbling fluidized beds. This appears to be counter-intuitive since much of the thermal transport process at the submerged heat transfer surface is presumed to be associated with contact between solid particles and the heat transfer surface. Nevertheless, experimental measurements such as those of Ziegler et al. (1964) indicate that the heat transfer coefficient was essentially independent of particle thermal conductivity and varied only mildly with particle heat capacity. These investigators measured heat transfer coefficients in bubbling fluidized beds of different metallic particles which had essentially the same solid density but varied in thermal conductivity by a factor of nine and in heat capacity by a factor of two. 

X-ray diffraction studies are usually carried out at room temperature under ambient conditions. It is possible, however, to perform variable-temperature XPD, wherein powder patterns are obtained while the sample is heated or cooled. Such studies are invaluable for identifying thermally induced or subambient phase transitions. Variable-temperature XPD was used to study the solid state properties of lactose [20], Fawcett et al. have developed an instrument that permits simultaneous XPD and differential scanning calorimetry on the same sample [21], The instrument was used to characterize a compound that was capable of existing in two polymorphic forms, whose melting points were 146°C (form II) and 150°C (form I). Form II was heated, and x-ray powder patterns were obtained at room temperature, at 145°C (form II had just started to melt), and at 148°C (Fig. 2 one characteristic peak each of form I and form II are identified). The x-ray pattern obtained at 148°C revealed melting of form II but partial recrystallization of form I. When the sample was cooled to 110°C and reheated to 146°C, only crystalline form I was observed. Through these experiments, the authors established that melting of form II was accompanied by recrystallization of form I. 

Cheng Z, Zha S, Aguilar L, and Liu M. Chemical, electrical, and thermal properties of strontium doped lanthanum vanadate. Solid State Ionics 2005 176 1921-1928. 

The concept of quantization enabled physicists to solve problems that nineteenth-century physics could not. One of these involved the thermal properties of solids when they are heated to incandescence. The other involved the induction of electrical current in metals when they are exposed to only specific frequencies of electromagnetic radiation. 

An LDPE resin was used for this study. The resin had a melt index of 2.0 dg/min (2.16 kg, 190 °C) and a solid density of 0.922 g/cmT The shear viscosity was reported previously [37] thermal properties are provided in Chapter 4 bulk density as a function of temperature and pressure is provided in Fig. 4.4 and the coefficients of dynamic friction are provided in Appendix A5. The lateral stress ratio was measured at 0.7 [38] using the device shown in Fig. 4.8. 

The forward search starts from the name of a chemical compound, proceeds to finding its molecular structure, and then its physical and chemical properties, such as the boiling point, melting point, density, etcetera, in a handbook. Many databases for single compounds are also organized by classes and families of similar structures. Fluid solutions represent the next level of complexity. For the most important fluids, such as water, air, and some refrigerants, we can find extensive tables for the thermal properties of mixtures. For complex fluids, such as paint and emulsion, which are difficult to characterize and to reproduce, specialized books and journals should be consulted. The properties of some crystalline solids can be found, but usually not for multicrystal composite and amorphous solids. 

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