Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
The zone-center optical phonons of layer materials GaSe, GaTe, and their solid solutions are studied by means of Raman scattering. Most of the structure in the hitherto unstudied spectrum of GaTe is identified by following their evolution in the solid solutions and relating them to already known bands in GaSe. Increas…
The dc conductivities of seven concentrated aqueous acids, and the electrical relaxation properties of four of these, are reported. At the glass transition temperature Tg, as determined by differential thermal analysis, the dc conductivities increase with Tg for the individual acids, according to an Arrhenius function…
Abstract Measurements have been made of the viscoelastic properties of a range of low-molecular-mass polystyrenes each having a narrow molecular mass distribution. Several experimental techniques using alternating shear have been employed covering the frequency range 10-2 Hz to 450 MHz and at temperatures from the gla…
The infrared reflection spectra of $\ensuremath{\alpha}\ensuremath{-}{\mathrm{Fe}}_{2}{\mathrm{O}}_{3}$ were measured in the energy range 30-1000 ${\mathrm{cm}}^{\ensuremath{-}1}$; two optical-phonon modes were observed for extraordinary ray; four optical-phonon modes were observed for ordinary ray. The optical consta…
Vitreous LiNbO3 and LiTaO3 have been prepared by roller quenching these compositions from the melt. The transparent glasses exhibit pronounced dielectric anomalies with peaks of ε≳105 close to the crystallization temperature which are not characteristic of the crystalline phase. Pyroelectricity is induced after coolin…
Polarized low-frequency Raman and Brillouin spectra of the chalcogenide glasses ${\mathrm{As}}_{2}$${\mathrm{S}}_{3}$, Ge${\mathrm{S}}_{2}$, Ge${\mathrm{Se}}_{2}$, and ${\mathrm{As}}_{2}$${\mathrm{Se}}_{3}$ and the glass alloy system ${({\mathrm{As}}_{2}{\mathrm{S}}_{3})}_{1\ensuremath{-}x}{(\mathrm{Ge}{\mathrm{S}}_{2…
The retarded polarization in an ensemble of ultrafine particles is incorporated in the Maxwell-Garnett theory for the average dielectric permeability of a system of randomly distributed particles. This theory is applied to the optical absorption of ultrafine silver particles in a glass matrix. For particles with mean…
Hopping motion is considered in a linear chain containing an arbitrary density of particles that are not allowed to hop to occupied sites. The general case of two inequivalent lattice sites $A$ and $B$ is treated. Transition-rate equations are solved by Monte Carlo simulation and, where possible, by analytic technique…
We have carried out a high-resolution x-ray-scattering study of the critical fluctuations in the nematic phase associated with the nematic-smectic-$A$ transition in N-$p$-cyanobenzylidene-$p$-octyloxyanilene (CBOOA). It is shown that for $8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}\ensuremath{\lesssim}\f…
A downfield shift of proton signals up to 9 ppm is induced in the 1H NMR spectra of juvenile hormone I (methyl 3,11-dimethyl-10,11-cis-epoxy-7-ethyl-2-trans, 6-trans-tridecadienoate) and III (methyl 10,11-epoxy-2-trans, 6-trans-farnesoate) by the lanthanide complex Eu(fod)3. A plot of induced shift vs the ratio of [LS…
Abstract High molecular weight poly(ethylene oxalate) with fiber‐forming properties was obtained from oxalic acid and ethylene glycol. The process was carried out on two stages in the melt. A new method was used for aliphatic oligoester synthesis in the melt, because the decomposition of oxalic acid takes place in the…
Rates of hydrolysis of water-soluble sodium pyrophosphate and sodium tripolyphosphate, applied to soil at 200 ppm P, were extremely rapid (about 2–7%/h) during the 0 to 24- or 0- to 48-h period following phosphate application but decreased with time of incubation. Rates of hydrolysis increased linearly and increased a…
Li2CdSiO4, Pmnb, a = 6.479(1), b = 10.715 (2), c = 5.119 (1) ,~, Z = 4, D,. = 4.08 g c m -3. Li, Si and Cd occupy the tetrahedral position of the wurzite structure in an ordered way. Introduction. Colourless crystals were grown from a LiCI melt containing CdO and SiO 2. Unit-cell and intensity data were measured on a…
When the film thickness is considered as a parameter, a system composed of a transparent film on an absorbing substrate (in a transparent ambient) is characterized by a range of principal angle ϕ¯min⩽ϕ¯⩽ϕ¯max over which the associated principal azimuth ψ¯ varies between 0° and 90° (i.e., 0°⩽ψ¯⩽90°) and the reflection…
Cellulose treated with a nitrogen-containing flame retardant was pyrolyzed under anaerobic conditions simulating the initial formation of gaseous material. The gaseous products were retained principally in the small sample loop, then the material in the sample loop was directed into a gas Chromatograph for separation.…
Ultrasonic attenuation has been measured in UF6 at room temperature over an f/P range of 20 kHz/atm to 70 MHz/atm. A single relaxation process was inferred with an isothermal relaxation time of 5.7×10−9 sec-atm. Assuming the three higher energy modes are coupled by fast transfer processes to the three lower energy mod…
The luminescence of Eu 3+ and Bi 3+ in the two modifications of is reported. The Eu 3+ ‐activated α‐phase (with olivine structure) shows a bright red luminescence at room temperature, whereas the Eu 3+ ‐activated β‐phase (with structure) shows a red luminescence of much lower intensity at room temperature. This differ…
Abstract Muconic acid (Mu‐acid) was found to polymerize to trans ‐1,4‐poly(Mu‐acid) with the use of azobisisobutyronitrile (AIBN) as an initiator. Similarly, a muconic acid derivative, ethyl muconate (EMu), was readily polymerized through a trans ‐1,4 addition mechanism by the use of a radical or anionic catalyst, but…
Tensile creep tests have been carried out on poly(vinyl chloride) with small amounts of dioctyl phthalate (DOP) and dioctyl adipate (DOA) at room temperature. Creep compliance, the stress limit of approximately linear viscoelasticity, and stress dilatation are reported as functions of additive content in the time rang…
Abstract Some physical and chemical properties of an ionic complex made from the weak polyelectrolytes carboxymethylated poly(vinyl alcohol) (PA) and aminoacetalized poly(vinyl alcohol) (PC) are investigated in comparison with those of another ionic complex made from the strong polyelectrolytes sulfated poly(vinyl alc…