Materials Literature
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The free energy of a polmyer solution is derived by a consideration of the monomer density fluctuations and incorporating three-body interactions. Explicit interpolation formulas are obtained for the concentration dependence of the correlation length for arbitrary strengths of two- and three-body interactions within t…
A universal but unexplained characteristic of glasses is the temperature-independent region or plateau in the thermal conductivity for temperatures 1--30 K. Examination of low-temperature thermal conductivity data for a wide variety of glasses indicates that the mean free path of the average thermal phonon becomes les…
The thermal conductivities of glassy solids, when scaled by material parameters, have a similar magnitude and temperature dependence, from the lowest temperatures yet measured, to the melt. Both empirical results and theoretical models are reviewed briefly. It is emphasized that the thermal conductivity of an amorphou…
Measurements of the elastic and inelastic neutron scattering from vitreous silica in the frequency range 0.3 to 4 THz and with scattering vectors in the range 0.2 to 5.3 A${\r{}}^{\mathrm{\ensuremath{-}}1}$ are analyzed in conjunction with heat-capacity measurements on the same samples to provide a microscopic descrip…
We present valence effective Hamiltonian (VEH) band-structure calculations on polyisothianaphthene and some of its simple derivatives. Our goal is to rationalize the lowering of the band gap by about 1 eV which is experimentally observed in polyisothianaphthene (Eg=∼1 eV) relative to the parent polymer, polythiophene…
The thermal conductivity of a monatomic face-centered-cubic lattice has been calculated over a range of temperatures from one-twentieth to one-half the melting temperature. An inverse-twelfth-power ``soft-sphere'' potential was used to represent the interatomic forces. We have examined, quantitatively, the approximati…
Piezoelectricity in pyroelectrics and the linear response of polarization to a strain gradient?lexoelectricity) are discussed in the framework of the unified approach. It was pointed out by Born and Huang and by Martin, that there was a difference between the piezoelectric response for the cases of a sound wave and of…
The electrochemical, physicochemical and adhesional aspects of corrosion protection by organic coatings are shortly discussed. Attention is drawn to some inconsistancies in the interpretation of protective mechanisms and suggestions are given how protective principles may be optimally realized in practical systems.
Polymeric materials are widely used to control the corrosion of metals, both to maintain appearance and to prevent loss of structural integrity. In this chapter, the fundamentals of metallic corrosion are briefly reviewed. Methods of studying corrosion, and of evaluating the performance of polymeric materials used in…
Organic coatings lose adherence to a metal substrate by many processes. The eventual consequence of this de-adhesion is corrosion of the metal beneath the coating. Among the important de-adhesion processes are: loss of adhesion when wet, cathodic delamination, cathodic blistering, swelling of the polymer, gas blisteri…
Polymeric materials are widely used to control the corrosion of metals, both to maintain appearance and to prevent loss of structural integrity. In this chapter, the fundamentals of metallic corrosion are briefly reviewed. Methods of studying corrosion, and of evaluating the performance of polymeric materials used in…
The optical constants of thin films of silver and titanium nitride have been obtained in the visible and near infrared spectral regions by the Nestell-Christy method. The silver films, 9-.27 nm thick, were prepared by d.c. magnetron sputtering at low pressures. It is found that the silver films, prepared at sputtering…
Cobalt nitride (CoNx) thin films with a large perpendicular magnetic anisotropy are synthesized by reactive sputtering. The perpendicular magnetic anisotropy is induced by substrate heating during deposition, annealing after deposition, or ion bombardment during deposition.
We report high-pressure, low-temperature x-ray scattering measurements on the organic conductor ${(\mathrm{TMTSF})}_{2}$Re${\mathrm{O}}_{4}$. The anion-ordering phase diagram has been established up to 17 kbar. In addition to the low-pressure phase characterized by the wave vector $q=(\frac{1}{2},\frac{1}{2},\frac{1}{…
Measurements of the specific heat of quasi one-dimensional conductors, ${(\mathrm{T}\mathrm{a}{\mathrm{Se}}_{4})}_{2}$I and ${(\mathrm{N}\mathrm{b}{\mathrm{Se}}_{4})}_{3}$I, between 0.1 and 8 K, are reported. Whereas no deviation from the ${T}^{3}$ law occurs at low temperature for ${(\mathrm{N}\mathrm{b}{\mathrm{Se}}…
Two Peierls instabilities with different critical temperatures and nearly equal wave vectors are considered in the limit of weak bilinear coupling. This coupling is important close to the first transition, when the unstable phonon induces the ordering at the same wave vector in the other phonon branch. The low-tempera…
Effects of lattice fluctuations on the charge-density-wave transition are studied for a three-dimensional system of the basis of a two-band model. Using the thermal Green function method the authors calculate the polarisation function for phonons and the self-energy for electrons in the mode-mode coupling approximatio…
An E.P.R. study of the luminescent state in the CaMoO4 crystal at 1·2 K with a 60–80 GHz spectrometer is reported. The spectra can be fitted with a spin hamiltonian for an orbitally nondegenerate triplet state with D = - 94·358 GHz and E = 32·697 GHz. The directions of the principal axes of the ZFS tensor indicate tha…
Sonicated calf thymus DNA with an average length of approximately 100 base pairs has been found to form a cholesteric liquid crystal at a concentration of approximately 250 mg of DNA/mL of solution. Immediately after preparation, small ordered domains of a few micrometers are formed, resulting in an opaque solution. T…
A theory of fracture in spatially varying anisotropic glass is developed to interpret electron micrographs of freeze-fractured surfaces of cholesteric samples. The expression for energy per unit area released by crack formation is $\ensuremath{\gamma}\ensuremath{\propto}{[\mathbf{n}\ifmmode\cdot\else\textperiodcentere…