Materials Literature
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The electrical resistivity and optical absorption of the layered dichalcogenides ${\mathrm{Ti}}_{x}{\mathrm{Ta}}_{1\ensuremath{-}x}{\mathrm{S}}_{2}$, ${\mathrm{Zr}}_{x}{\mathrm{Ta}}_{1\ensuremath{-}x}{\mathrm{S}}_{2}$, and ${\mathrm{Ti}}_{x}{\mathrm{Nb}}_{1\ensuremath{-}x}{\mathrm{Se}}_{2}$ ($0\ensuremath{\leqq}x\ensu…
The infrared spectrum of gaseous N2O4 was obtained under conditions which allowed study of both strongly and weakly absorbing features. These spectral features were assigned with the aid of vibration-rotation band shape theory. Weakly absorbing sequence bands were identified which contain torsional vibrations. The roc…
A new nematic material in which ε∥ exhibits a dielectric loss in the audio-frequency range is reported. At 25 °C Δ ε=(ε∥−ε⊥) reverses sign at 2.5 kHz and can be as positive as 6.2 at low frequencies and as negative as −2.2 at high frequencies; the activation energy for the loss is 0.91 eV. The availability of a dielec…
X-ray-diffraction radial-distribution, electron-spectroscopy-for-chemical-analysis (ESCA), crystallization, and differential-thermal-analysis (DTA) studies of glassy ${\mathrm{Cu}}_{x}{({\mathrm{As}}_{0.4}{\mathrm{Se}}_{0.6})}_{100\ensuremath{-}x}$ alloys, with 0 \ensuremath{\le} \ifmmode\times\else\texttimes\fi{} \en…
The driving force in electromigration is generally assumed to consist of a "direct force" due to the applied field and an "electron-wind" term due to momentum exchange with the current carriers. In the case of the "direct force" it is uncertain how effectively the charge is screened. In the case of the "electron wind"…
The bond-orbital model is reformulated taking explicit account of the large overlap of two hybrids in the same bond rather than absorbing it in a pseudopotential. This gives a correction to the cohesive energy but other changes are absorbed in the ${V}_{1}$, ${V}_{2}$, and ${V}_{3}$ for each material. These parameters…
The temperature dependence of the dc electrical conductivity of tetrathiofulvalinium tetracyanoquinodimethan (TTF)(TCNQ) measured along the crystallographic $a$, $b$, and ${c}^{*}$ axes and the corresponding anisotropies $\frac{{\ensuremath{\sigma}}_{\ensuremath{\parallel}}^{b}}{{\ensuremath{\sigma}}_{\ensuremath{\per…
The temperature dependence of the infrared reflectivity of rutile, Ti${\mathrm{O}}_{2}$, is reported in the range 275-900 ${\mathrm{cm}}_{\ensuremath{-}1}$ and from room temperature up to 1500 K, for both the ${A}_{2u}$- and ${E}_{u}$-type mode spectra. Reflectivity spectra are fitted with the aid of a four-parameter…
Elasticity theory is applied to nematic liquid crystals with particular boundary conditions. The calculus of variations is used to derive the torque equations, the solutions of which are found by relaxation methods on a digital computer. These solutions are used to draw pictures of the molecular arrangements and with…
The conductivity of single crystals of tetrathiafulvalene-tetracyanoquinodimethane (TTF-TCNQ) was measured over the temperature range 40-300 K. The maximum low-temperature conductivity parallel to the $b$ axis ranged from 12-35 times the corresponding room-temperature value. The temperature dependence of the intrinsic…
Abstract X‐ray measurements as function of temperature were made from pure polyvinyl alcohol (PVA) and concentrated PVA‐solutions in water, glycerine, and glycol. The solutions form gels at adequate low temperatures. As the formation of a chemically bound network can be excluded gel formation must be related to physic…
The regeneration of cellulose from solutions in 85 percent phosphoric acid into glycerol at 170 degrees C resulted in its recovery wholly in the native or cellulose I lattice. Identification of the structure of the regenerated material is based on comparisons of its x-ray diffractogram and its Raman spectrum with thos…
The piezoelectric switching of antiferroelectric domains by the simultaneous application of an electric field E i and mechanical stress T jk is proposed as a direct method for examining whether some spinel compositions do have point symmetry 43m and concomitant antiferroelectric ordering as proposed by Grimes (see abs…
A method that can be easily programmed on a digital computer is presented for optimizing the design of dielectric multilayer filters. Certain rules have been formulated to allow one to construct the electric field transmittance explicitly for any thin film filter system. From the spectral distribution of transmittance…
The tearing energy theory developed to describe the failure properties of vulcanized rubbers is shown to be applicable to the cut growth and fatigue properties of cellular polyurethanes. The effective inherent flaw size to initiate cut growth in the cellular polyurethane predicted from fatigue results has been found t…
Calorimetric and dielectric measurements have been made on Rb${\mathrm{H}}_{2}$As${\mathrm{O}}_{4}$ in the vicinity of the temperature of the ferroelectric transition 109.75 K. The transition is found to be first order with latent heat 255 \ifmmode\pm\else\textpm\fi{} 5 J/mole. The total transition entropy is found to…
Different polyamides and polysulfonamides were prepared by the interfacial polycondensation method. The influence of the experimental condition was specified. The principal characteristics of polymers are indicated (solubilities, molecular weights, IR spectra, thermal stability). In the case of poly(ethylene 1,3-benze…
The use of the nephelauxetic ratio for the calculation of percent covalency is examined. Values of Fk and Ek obtained from four parameter fits (e.g. F 2, F 4, F 6 and ζ4f) neglecting configuration interaction for Pr3+ in various host lattices are compared to those of the free ion. By including the effects of 4f-ligand…
We have carefully determined the optical spectrum of ${\mathrm{K}}_{2}$Pt${(\mathrm{CN})}_{4}$${\mathrm{Br}}_{0.3}$ \ifmmode\cdot\else\textperiodcentered\fi{} 3${\mathrm{H}}_{2}$ O near the reflectivity edge. Our data reveal, in addition to the expected monotonic background, a broad peak in ${\ensuremath{\epsilon}}_{2…
Knitting machine settings and their effect on fabric distortion are examined, and this information is related to finishing procedures involving heat setting and chemical finishing systems. Experiments with a cotton/polyester double knit show that acceptable shrinkage values can be achieved by a combination of careful…